diff --git a/src/sync/export.rs b/src/sync/export.rs
index 12ec7f2..d3cadfe 100644
--- a/src/sync/export.rs
+++ b/src/sync/export.rs
@@ -1,5 +1,6 @@
 /*
  * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
+ * SPDX-FileCopyrightText: 2026 John Coffey <johnellis@linux.com>
  *
  * SPDX-License-Identifier: Apache-2.0 OR MIT
  */
@@ -97,6 +98,34 @@ impl<'a> Uploader<'a> {
         Ok(id)
     }
 
+    /// As `upload_with`, but sends `bytes` in place of the stored blob: for
+    /// content rewritten on its way to the target. Cached under the same
+    /// local id, so a retry sends the rewritten bytes again.
+    fn upload_bytes_as(
+        &mut self,
+        local_id: i64,
+        content_type: &str,
+        bytes: &[u8],
+    ) -> Result<JmapId, JmapError> {
+        self.touched.push(local_id);
+        if let Some(id) = self.cache.get(&local_id) {
+            return Ok(id.clone());
+        }
+        let id = if self.net.dry_run {
+            JmapId(format!("dryrun-blob-{local_id}"))
+        } else {
+            blobxfer::upload_bytes(
+                &self.net.client,
+                &self.net.session,
+                &self.net.account,
+                content_type,
+                bytes,
+            )?
+        };
+        self.cache.insert(local_id, id.clone());
+        Ok(id)
+    }
+
     fn invalidate(&mut self, local_id: i64) {
         self.cache.remove(&local_id);
     }
@@ -435,6 +464,8 @@ mod keyed;
 
 mod sieve;
 
+mod sieve_names;
+
 mod uidtype;
 
 mod email;
diff --git a/src/sync/export/sieve.rs b/src/sync/export/sieve.rs
index 8928202..5420559 100644
--- a/src/sync/export/sieve.rs
+++ b/src/sync/export/sieve.rs
@@ -1,5 +1,6 @@
 /*
  * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
+ * SPDX-FileCopyrightText: 2026 John Coffey <johnellis@linux.com>
  *
  * SPDX-License-Identifier: Apache-2.0 OR MIT
  */
@@ -9,10 +10,12 @@ use std::collections::{HashMap, HashSet};
 use serde_json::{Value, json};
 
 use super::common::{create_batch, jid, retry_if_blob_missing, target_get_all};
+use super::sieve_names;
 use super::{Maps, Net, Plan, Uploader};
 use crate::error::Error;
-use crate::jmap::request::Request;
-use crate::logging::Logger;
+use crate::jmap::request::{Request, check_method_error};
+use crate::logging::{LEVEL_DEFAULT, Logger};
+use crate::sync::import_jmap::mapping::BlobBytes;
 use crate::sync::import_jmap::mapping::{SIEVE_SELECT, row_to_sieve_script};
 use crate::sync::{Context, TypeCounts};
 use crate::types::ObjectType;
@@ -57,6 +60,11 @@ pub fn reconcile(
     let mut active_target: Option<String> = None;
     let mut deactivate = false;
     let mut uploader = Uploader::new(net, &ctx.conn);
+    let rename_vendor = sieve_names::target_uses_inbuxa_names(&target_sieve_extensions(net));
+    let wanted_active = locals
+        .iter()
+        .find(|(_, _, a, _)| *a)
+        .map(|(_, n, _, _)| n.clone().unwrap_or_default());
 
     for (local, name, is_active, blob_local) in &locals {
         let matched = name.as_ref().and_then(|n| target_by_name.get(n)).cloned();
@@ -65,10 +73,18 @@ pub fn reconcile(
             id
         } else {
             let cid = format!("c{local}");
+            let label = name.as_deref().unwrap_or("(unnamed)");
+            let rewritten = if rename_vendor {
+                renamed_script(&uploader, *blob_local, label, logger)?
+            } else {
+                None
+            };
             let build = |up: &mut Uploader<'_>| -> Result<Value, Error> {
-                let blob_id = up
-                    .upload_with(*blob_local, "application/sieve")
-                    .map_err(Error::from)?;
+                let blob_id = match &rewritten {
+                    Some(bytes) => up.upload_bytes_as(*blob_local, "application/sieve", bytes),
+                    None => up.upload_with(*blob_local, "application/sieve"),
+                }
+                .map_err(Error::from)?;
                 let mut obj = serde_json::Map::new();
                 if let Some(n) = name {
                     obj.insert("name".to_owned(), Value::String(n.clone()));
@@ -92,7 +108,7 @@ pub fn reconcile(
                 }
                 None => {
                     for (cid, err) in &outcome.not_created {
-                        logger.warn(&format!("SieveScript {cid} not created: {err}"));
+                        logger.warn(&format!("SieveScript {label} ({cid}) not created: {err}"));
                     }
                     counts.failed += 1;
                     continue;
@@ -107,6 +123,15 @@ pub fn reconcile(
     if active_target.is_none() && locals.iter().all(|(_, _, a, _)| !*a) {
         deactivate = true;
     }
+    if let (Some(name), None) = (&wanted_active, &active_target) {
+        // The script that was active at the source never made it to the
+        // target (its creation failure is already counted): say plainly that
+        // the account now has no filtering, rather than leave it to a warning.
+        logger.error(&format!(
+            "the active Sieve script \"{name}\" could not be created on the target; \
+             no filtering is active there"
+        ));
+    }
 
     if !net.dry_run {
         let mut req = Request::new();
@@ -118,8 +143,20 @@ pub fn reconcile(
             json!({ "accountId": net.account })
         };
         req.call("SieveScript/set", args, "a");
-        if let Err(e) = req.send(&net.client, &net.api) {
-            logger.warn(&format!("SieveScript activation failed: {e}"));
+        let result = req
+            .send(&net.client, &net.api)
+            .and_then(|resp| resp.by_call_id("a").cloned())
+            .and_then(|mr| check_method_error(&mr));
+        if let Err(e) = result {
+            match (&active_target, &wanted_active) {
+                (Some(_), Some(name)) => {
+                    logger.error(&format!(
+                        "the Sieve script \"{name}\" was created but could not be activated: {e}"
+                    ));
+                    counts.failed += 1;
+                }
+                _ => logger.warn(&format!("SieveScript activation failed: {e}")),
+            }
         }
     }
 
@@ -136,3 +173,39 @@ pub fn reconcile(
         active_sieve_target: active_target,
     })
 }
+
+/// The target's `sieveExtensions`, from its Sieve account capability.
+fn target_sieve_extensions(net: &Net) -> Vec<String> {
+    net.session
+        .account_capabilities(&net.account)
+        .and_then(|caps| caps.get("urn:ietf:params:jmap:sieve"))
+        .and_then(|c| c.get("sieveExtensions"))
+        .and_then(Value::as_array)
+        .map(|a| {
+            a.iter()
+                .filter_map(Value::as_str)
+                .map(str::to_owned)
+                .collect()
+        })
+        .unwrap_or_default()
+}
+
+/// The script's bytes with Stalwart's vendor names renamed for an inbuxa
+/// target, or `None` when it needs no change. Each rename is logged.
+fn renamed_script(
+    uploader: &Uploader<'_>,
+    blob_local: i64,
+    label: &str,
+    logger: &Logger,
+) -> Result<Option<Vec<u8>>, Error> {
+    let bytes = uploader.bytes(blob_local).map_err(Error::from)?;
+    Ok(sieve_names::rewrite(&bytes).map(|(out, renamed)| {
+        for old in &renamed {
+            let new = old.replacen("vnd.stalwart.", "vnd.inbuxa.", 1);
+            if logger.enabled(LEVEL_DEFAULT) {
+                eprintln!("export: SieveScript {label}: renamed {old} to {new}");
+            }
+        }
+        out
+    }))
+}
diff --git a/src/sync/export/sieve_names.rs b/src/sync/export/sieve_names.rs
new file mode 100644
index 0000000..0849403
--- /dev/null
+++ b/src/sync/export/sieve_names.rs
@@ -0,0 +1,342 @@
+/*
+ * SPDX-FileCopyrightText: 2026 John Coffey <johnellis@linux.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ */
+
+//! Stalwart's vendor Sieve names, renamed for inbuxa.
+//!
+//! inbuxa accepts `vnd.inbuxa.while` and `vnd.inbuxa.expressions` where
+//! Stalwart accepted `vnd.stalwart.*`, with no alias, and names its
+//! environment items the same way. A script carried over unchanged fails to
+//! compile on inbuxa, so export renames those names -- and only those names:
+//! the strings of a `require` list, the name argument of an `environment`
+//! test, and `${env.vnd.stalwart.…}` references inside strings. Everything
+//! else in the script, including other strings that happen to contain the
+//! text, is copied byte for byte.
+
+const OLD: &str = "vnd.stalwart.";
+const NEW: &str = "vnd.inbuxa.";
+const OLD_ENV_REF: &str = "${env.vnd.stalwart.";
+const NEW_ENV_REF: &str = "${env.vnd.inbuxa.";
+
+/// Whether the target advertises inbuxa's vendor extensions, from the
+/// `sieveExtensions` list of its `urn:ietf:params:jmap:sieve` account
+/// capability.
+pub fn target_uses_inbuxa_names(sieve_extensions: &[String]) -> bool {
+    sieve_extensions.iter().any(|e| e.starts_with(NEW))
+}
+
+/// The script with Stalwart's vendor names renamed, and the old names that
+/// were changed, in order. `None` when nothing needed renaming, or when the
+/// script is not UTF-8 (left alone rather than guessed at).
+pub fn rewrite(script: &[u8]) -> Option<(Vec<u8>, Vec<String>)> {
+    let text = std::str::from_utf8(script).ok()?;
+    if !text.contains(OLD) {
+        return None;
+    }
+    let mut out = String::with_capacity(text.len());
+    let mut renamed = Vec::new();
+    let mut copied = 0;
+    let mut context = Context::None;
+    for tok in Tokens::new(text) {
+        match tok.kind {
+            Kind::Word => {
+                context = match tok.text(text).to_ascii_lowercase().as_str() {
+                    "require" => Context::Require,
+                    "environment" => Context::Environment,
+                    _ if context == Context::Environment => Context::Environment,
+                    _ => Context::None,
+                };
+            }
+            Kind::Tag => {
+                // `environment :comparator "i;octet"`: the comparator's own
+                // string is not the item name.
+                if context == Context::Environment
+                    && tok.text(text).eq_ignore_ascii_case(":comparator")
+                {
+                    context = Context::EnvironmentComparator;
+                }
+            }
+            Kind::Quoted | Kind::Multiline => {
+                let (start, end) = tok.content;
+                let content = &text[start..end];
+                let mut replacement: Option<String> = None;
+                let whole_name = matches!(context, Context::Require | Context::Environment);
+                if whole_name && content.starts_with(OLD) {
+                    replacement = Some(format!("{NEW}{}", &content[OLD.len()..]));
+                    renamed.push(content.to_owned());
+                }
+                let current = replacement.as_deref().unwrap_or(content);
+                if current.contains(OLD_ENV_REF) {
+                    let mut n = 0;
+                    let mut rest = current;
+                    while let Some(i) = rest.find(OLD_ENV_REF) {
+                        let tail = &rest[i + 2..];
+                        let name_end = tail.find('}').unwrap_or(tail.len());
+                        renamed.push(tail[4..name_end].to_owned());
+                        rest = &rest[i + OLD_ENV_REF.len()..];
+                        n += 1;
+                    }
+                    if n > 0 {
+                        replacement = Some(current.replace(OLD_ENV_REF, NEW_ENV_REF));
+                    }
+                }
+                if let Some(r) = replacement {
+                    out.push_str(&text[copied..start]);
+                    out.push_str(&r);
+                    copied = end;
+                }
+                context = match context {
+                    Context::Require => Context::Require,
+                    Context::EnvironmentComparator => Context::Environment,
+                    _ => Context::None,
+                };
+            }
+            Kind::Punct(';') | Kind::Punct('{') | Kind::Punct('}') => context = Context::None,
+            Kind::Punct(_) => {}
+        }
+    }
+    if renamed.is_empty() {
+        return None;
+    }
+    out.push_str(&text[copied..]);
+    Some((out.into_bytes(), renamed))
+}
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum Context {
+    None,
+    Require,
+    Environment,
+    EnvironmentComparator,
+}
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum Kind {
+    Word,
+    Tag,
+    Quoted,
+    Multiline,
+    Punct(char),
+}
+
+struct Token {
+    kind: Kind,
+    span: (usize, usize),
+    /// The string's content, without quotes or the `text:` framing.
+    content: (usize, usize),
+}
+
+impl Token {
+    fn text<'a>(&self, src: &'a str) -> &'a str {
+        &src[self.span.0..self.span.1]
+    }
+}
+
+/// Just enough of RFC 5228's lexer to find strings and the words before
+/// them: comments are skipped, and quoted strings and `text:` blocks are
+/// read whole, so nothing inside them is mistaken for a command.
+struct Tokens<'a> {
+    src: &'a str,
+    pos: usize,
+}
+
+impl<'a> Tokens<'a> {
+    fn new(src: &'a str) -> Self {
+        Tokens { src, pos: 0 }
+    }
+}
+
+impl Iterator for Tokens<'_> {
+    type Item = Token;
+
+    fn next(&mut self) -> Option<Token> {
+        let b = self.src.as_bytes();
+        loop {
+            while self.pos < b.len() && b[self.pos].is_ascii_whitespace() {
+                self.pos += 1;
+            }
+            if self.pos >= b.len() {
+                return None;
+            }
+            if b[self.pos] == b'#' {
+                while self.pos < b.len() && b[self.pos] != b'\n' {
+                    self.pos += 1;
+                }
+                continue;
+            }
+            if b[self.pos..].starts_with(b"/*") {
+                self.pos = match self.src[self.pos + 2..].find("*/") {
+                    Some(i) => self.pos + 2 + i + 2,
+                    None => b.len(),
+                };
+                continue;
+            }
+            break;
+        }
+        let start = self.pos;
+        let c = b[start];
+        if c == b'"' {
+            let mut i = start + 1;
+            while i < b.len() && b[i] != b'"' {
+                i += if b[i] == b'\\' { 2 } else { 1 };
+            }
+            let end = i.min(b.len());
+            self.pos = (end + 1).min(b.len());
+            return Some(Token {
+                kind: Kind::Quoted,
+                span: (start, self.pos),
+                content: (start + 1, end),
+            });
+        }
+        if c.is_ascii_alphabetic() || c == b'_' || c == b':' {
+            let mut i = start + 1;
+            while i < b.len() && (b[i].is_ascii_alphanumeric() || b[i] == b'_') {
+                i += 1;
+            }
+            let word = &self.src[start..i];
+            if word.eq_ignore_ascii_case("text:")
+                || (word.eq_ignore_ascii_case("text") && b.get(i) == Some(&b':'))
+            {
+                let after = if b.get(i) == Some(&b':') { i + 1 } else { i };
+                // The body starts after the rest of the `text:` line and runs
+                // to a line holding a single dot.
+                let body = match self.src[after..].find('\n') {
+                    Some(n) => after + n + 1,
+                    None => b.len(),
+                };
+                let (body_end, next) = find_dot_line(self.src, body);
+                self.pos = next;
+                return Some(Token {
+                    kind: Kind::Multiline,
+                    span: (start, next),
+                    content: (body, body_end),
+                });
+            }
+            self.pos = i;
+            let kind = if c == b':' { Kind::Tag } else { Kind::Word };
+            return Some(Token {
+                kind,
+                span: (start, i),
+                content: (start, i),
+            });
+        }
+        let ch = self.src[start..].chars().next().unwrap_or('\0');
+        self.pos = start + ch.len_utf8();
+        Some(Token {
+            kind: Kind::Punct(ch),
+            span: (start, self.pos),
+            content: (start, self.pos),
+        })
+    }
+}
+
+/// End of a `text:` body (the start of its closing dot line) and the offset
+/// after that line.
+fn find_dot_line(src: &str, from: usize) -> (usize, usize) {
+    let mut line_start = from;
+    while line_start < src.len() {
+        let line_end = src[line_start..]
+            .find('\n')
+            .map(|n| line_start + n)
+            .unwrap_or(src.len());
+        if src[line_start..line_end].trim_end_matches('\r') == "." {
+            return (line_start, (line_end + 1).min(src.len()));
+        }
+        line_start = line_end + 1;
+    }
+    (src.len(), src.len())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn run(s: &str) -> Option<(String, Vec<String>)> {
+        rewrite(s.as_bytes()).map(|(b, r)| (String::from_utf8(b).unwrap(), r))
+    }
+
+    #[test]
+    fn renames_a_require_list() {
+        let (out, renamed) =
+            run("require [\"fileinto\", \"vnd.stalwart.while\", \"vnd.stalwart.expressions\"];\n")
+                .unwrap();
+        assert_eq!(
+            out,
+            "require [\"fileinto\", \"vnd.inbuxa.while\", \"vnd.inbuxa.expressions\"];\n"
+        );
+        assert_eq!(renamed, ["vnd.stalwart.while", "vnd.stalwart.expressions"]);
+    }
+
+    #[test]
+    fn renames_a_single_require_string() {
+        let (out, _) = run("REQUIRE \"vnd.stalwart.while\";").unwrap();
+        assert_eq!(out, "REQUIRE \"vnd.inbuxa.while\";");
+    }
+
+    #[test]
+    fn renames_the_environment_item_name_only() {
+        let src = "if environment :comparator \"i;octet\" :is \"vnd.stalwart.username\" \"vnd.stalwart.x\" { keep; }";
+        let (out, renamed) = run(src).unwrap();
+        assert_eq!(
+            out,
+            "if environment :comparator \"i;octet\" :is \"vnd.inbuxa.username\" \"vnd.stalwart.x\" { keep; }"
+        );
+        assert_eq!(renamed, ["vnd.stalwart.username"]);
+    }
+
+    #[test]
+    fn renames_env_references_inside_strings() {
+        let src = "set \"box\" \"${env.vnd.stalwart.default_mailbox}/Archive\";";
+        let (out, renamed) = run(src).unwrap();
+        assert_eq!(
+            out,
+            "set \"box\" \"${env.vnd.inbuxa.default_mailbox}/Archive\";"
+        );
+        assert_eq!(renamed, ["vnd.stalwart.default_mailbox"]);
+    }
+
+    #[test]
+    fn renames_env_references_in_text_blocks() {
+        let src = "vacation text:\nHi ${env.vnd.stalwart.username}.\n.\n;\n";
+        let (out, _) = run(src).unwrap();
+        assert_eq!(
+            out,
+            "vacation text:\nHi ${env.vnd.inbuxa.username}.\n.\n;\n"
+        );
+    }
+
+    #[test]
+    fn leaves_unrelated_strings_comments_and_text_alone() {
+        let src = "# vnd.stalwart.while is old\n/* \"vnd.stalwart.x\" */\n\
+                   if header :contains \"subject\" \"vnd.stalwart.while\" { fileinto \"vnd.stalwart.box\"; }\n\
+                   vacation text:\nrequire \"vnd.stalwart.while\";\n.\n;\n";
+        assert!(run(src).is_none());
+    }
+
+    #[test]
+    fn require_context_ends_at_the_semicolon() {
+        let src = "require \"fileinto\"; fileinto \"vnd.stalwart.folder\";";
+        assert!(run(src).is_none());
+    }
+
+    #[test]
+    fn nothing_to_do_is_none() {
+        assert!(run("require \"fileinto\";\nkeep;\n").is_none());
+        assert!(rewrite(&[0xff, 0xfe, b'v']).is_none());
+    }
+
+    #[test]
+    fn target_detection() {
+        assert!(target_uses_inbuxa_names(&[
+            "fileinto".to_owned(),
+            "vnd.inbuxa.while".to_owned()
+        ]));
+        assert!(!target_uses_inbuxa_names(&[
+            "fileinto".to_owned(),
+            "vnd.stalwart.while".to_owned()
+        ]));
+        assert!(!target_uses_inbuxa_names(&[]));
+    }
+}
diff --git a/tests/mock_sync.rs b/tests/mock_sync.rs
index 2bd9546..8c545f4 100644
--- a/tests/mock_sync.rs
+++ b/tests/mock_sync.rs
@@ -2683,6 +2683,205 @@ fn export_sieve_script_matches_by_name_not_content() {
     let _ = std::fs::remove_file(&archive);
 }
 
+/// A session like `session_body_full`, whose Sieve capability lists
+/// `extensions` in `sieveExtensions`.
+fn session_body_sieve(base: &str, extensions: &[&str]) -> String {
+    let mut v: serde_json::Value = serde_json::from_str(&session_body_full(base)).unwrap();
+    v["accounts"]["w"]["accountCapabilities"]["urn:ietf:params:jmap:sieve"] =
+        json!({ "sieveExtensions": extensions });
+    v.to_string()
+}
+
+/// One active script `name` in a fresh archive, with `body` as its content.
+fn archive_with_active_sieve(name: &str, body: &[u8]) -> PathBuf {
+    let archive = tmp();
+    let conn = db::init::open(&archive).unwrap();
+    let blob = db::blobs::intern_blob(&conn, body).unwrap();
+    conn.execute(
+        "INSERT INTO sieve_scripts (id,name,is_active,blob_id) VALUES (1,?1,1,?2)",
+        rusqlite::params![name, blob],
+    )
+    .unwrap();
+    archive
+}
+
+/// Mocks for exporting one script to an empty target: get, upload (matched
+/// by `upload_body`), create, and activation answered with `activation`.
+/// Returns the upload mock and the activation mock.
+fn mock_sieve_export(
+    server: &mut mockito::ServerGuard,
+    session: String,
+    upload_body: Matcher,
+    create_ok: bool,
+    activation: serde_json::Value,
+) -> (mockito::Mock, mockito::Mock, Vec<mockito::Mock>) {
+    let api = "/jmap/api";
+    let mut keep = vec![
+        server.mock("GET", "/").with_status(404).create(),
+        server
+            .mock("GET", "/.well-known/jmap")
+            .with_body(session)
+            .expect_at_least(1)
+            .create(),
+        server
+            .mock("POST", api)
+            .match_body(Matcher::Regex("SieveScript/get".into()))
+            .with_body(
+                json!({"methodResponses":[["SieveScript/get",
+                    {"accountId":"w","list":[],"notFound":[]},"g"]]})
+                .to_string(),
+            )
+            .create(),
+    ];
+    let upload = server
+        .mock("POST", Matcher::Regex("/jmap/upload/".into()))
+        .match_body(upload_body)
+        .with_body(json!({"blobId":"UPN"}).to_string())
+        .expect(1)
+        .create();
+    let created = if create_ok {
+        json!({"accountId":"w","created":{"c1":{"id":"S1"}}})
+    } else {
+        json!({"accountId":"w","notCreated":{"c1":{"type":"invalidScript",
+            "description":"unknown extension"}}})
+    };
+    keep.push(
+        server
+            .mock("POST", api)
+            .match_body(Matcher::AllOf(vec![
+                Matcher::Regex("SieveScript/set".into()),
+                Matcher::Regex("\"create\"".into()),
+            ]))
+            .with_body(json!({"methodResponses":[["SieveScript/set", created, "s"]]}).to_string())
+            .create(),
+    );
+    let activate = server
+        .mock("POST", api)
+        .match_body(Matcher::AllOf(vec![
+            Matcher::Regex("SieveScript/set".into()),
+            Matcher::Regex("onSuccess".into()),
+        ]))
+        .with_body(json!({"methodResponses":[activation]}).to_string())
+        .expect(1)
+        .create();
+    (upload, activate, keep)
+}
+
+fn sieve_counts(summary: &sync::Summary) -> sync::TypeCounts {
+    summary
+        .per_type
+        .iter()
+        .find(|(t, _)| *t == "SieveScript")
+        .map(|(_, c)| c.clone())
+        .expect("sieve counts")
+}
+
+#[test]
+fn export_sieve_renames_stalwart_names_for_an_inbuxa_target() {
+    let mut server = mockito::Server::new();
+    let base = server.url();
+    let archive = archive_with_active_sieve(
+        "loop",
+        b"require [\"fileinto\", \"vnd.stalwart.while\"];\nkeep;\n",
+    );
+    let (upload, activate, _keep) = mock_sieve_export(
+        &mut server,
+        session_body_sieve(
+            &base,
+            &["fileinto", "vnd.inbuxa.while", "vnd.inbuxa.expressions"],
+        ),
+        Matcher::Exact("require [\"fileinto\", \"vnd.inbuxa.while\"];\nkeep;\n".into()),
+        true,
+        json!(["SieveScript/set", {"accountId":"w"}, "a"]),
+    );
+    let summary = sync::export::run(
+        common(&archive),
+        export_cfg_objects(&base, vec![ObjectType::SieveScript]),
+    )
+    .expect("export");
+    upload.assert();
+    activate.assert();
+    let c = sieve_counts(&summary);
+    assert_eq!((c.created, c.failed), (1, 0));
+    let _ = std::fs::remove_file(&archive);
+}
+
+#[test]
+fn export_sieve_keeps_stalwart_names_for_a_target_without_inbuxa_names() {
+    let mut server = mockito::Server::new();
+    let base = server.url();
+    let archive = archive_with_active_sieve(
+        "loop",
+        b"require [\"fileinto\", \"vnd.stalwart.while\"];\nkeep;\n",
+    );
+    let (upload, _activate, _keep) = mock_sieve_export(
+        &mut server,
+        session_body_sieve(&base, &["fileinto", "vnd.stalwart.while"]),
+        Matcher::Regex("vnd\\.stalwart\\.while".into()),
+        true,
+        json!(["SieveScript/set", {"accountId":"w"}, "a"]),
+    );
+    let summary = sync::export::run(
+        common(&archive),
+        export_cfg_objects(&base, vec![ObjectType::SieveScript]),
+    )
+    .expect("export");
+    upload.assert();
+    assert_eq!(sieve_counts(&summary).failed, 0);
+    let _ = std::fs::remove_file(&archive);
+}
+
+#[test]
+fn export_sieve_activation_error_is_a_failure() {
+    let mut server = mockito::Server::new();
+    let base = server.url();
+    let archive = archive_with_active_sieve("main", b"require [\"fileinto\"];\nkeep;\n");
+    let (_upload, activate, _keep) = mock_sieve_export(
+        &mut server,
+        session_body_full(&base),
+        Matcher::Any,
+        true,
+        json!(["error", {"type":"invalidArguments","description":"cannot activate"}, "a"]),
+    );
+    let summary = sync::export::run(
+        common(&archive),
+        export_cfg_objects(&base, vec![ObjectType::SieveScript]),
+    )
+    .expect("export");
+    activate.assert();
+    let c = sieve_counts(&summary);
+    assert_eq!(c.created, 1);
+    assert_eq!(
+        c.failed, 1,
+        "a failed activation is a failure, not a warning"
+    );
+    assert!(summary.any_failed(), "so export exits non-zero");
+    let _ = std::fs::remove_file(&archive);
+}
+
+#[test]
+fn export_sieve_active_script_not_created_is_a_failure() {
+    let mut server = mockito::Server::new();
+    let base = server.url();
+    let archive = archive_with_active_sieve("main", b"require [\"nope\"];\nkeep;\n");
+    let (_upload, _activate, _keep) = mock_sieve_export(
+        &mut server,
+        session_body_full(&base),
+        Matcher::Any,
+        false,
+        json!(["SieveScript/set", {"accountId":"w"}, "a"]),
+    );
+    let summary = sync::export::run(
+        common(&archive),
+        export_cfg_objects(&base, vec![ObjectType::SieveScript]),
+    )
+    .expect("export");
+    let c = sieve_counts(&summary);
+    assert_eq!((c.created, c.failed), (0, 1));
+    assert!(summary.any_failed());
+    let _ = std::fs::remove_file(&archive);
+}
+
 #[test]
 fn export_sieve_scripts_identical_content_different_names_both_created() {
     let mut server = mockito::Server::new();