Sieve script creation error

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1

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Hi,

Stalwart 0.16.11 in a VM.
I’m trying to set a Sieve script in the Stalwart account page and it is not working.
In the Trace log I’m seeing this error:
2026-07-03T09:29:30Z TRACE HTTP request body (http.request-body) listenerId = “https”, localPort = 443, remoteIp = 10.2.1.19, remotePort = 51716, details = [[“host”, “mail.example.ro”], [“connection”, “keep-alive”], [“content-length”, “428”], [“sec-ch-ua-platform”, ““Windows””], [“authorization”, “Bearer sw1.gLK-vpNZF9Bo5J1-sS5uYxiTmFH_tetVE4URMoJSrezPE1_RTwc8MY_dSBnu_lJH8w.YW5kcmVpLm1pcm9uQHJlY2VwdGl2LnJv”], [“user-agent”, “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36”], [“sec-ch-ua”, ““Brave”;v=“149”, “Chromium”;v=“149”, “Not)A;Brand”;v=“24"”], [“content-type”, “application/json”], [“sec-ch-ua-mobile”, “?0”], [“accept”, “/”], [“sec-gpc”, “1”], [“accept-language”, “en-US,en;q=0.9”], [“origin”, “https://mail.example.ro”], [“sec-fetch-site”, “same-origin”], [“sec-fetch-mode”, “cors”], [“sec-fetch-dest”, “empty”], [“referer”, “https://mail.example.ro/admin/Account/SieveScript/new”], [“accept-encoding”, “gzip, deflate, br, zstd”]], contents = “{“using”:[“urn:ietf:params:jmap:core”,“urn:stalwart:jmap”],“methodCalls”:[[“Blob/upload”,{“accountId”:“c”,“create”:{“temp-blob-0”:{“data”:[{“data:asText”:“require \“fileinto\”;\n\nif address :is \“From\” \“test@testingro\” {\n fileinto \“Trash\”;\n}”}],“type”:“application/octet-stream”}}},“blob-0”],[“SieveScript/set”,{“accountId”:“c”,“create”:{“new-0”:{“blobId”:”#temp-blob-0”,“isActive”:true,“name”:“cPanel”}}},“set-0”]]}", size = 428
2026-07-03T09:29:30Z DEBUG Invalid JMAP result reference (jmap.invalid-result-reference) listenerId = “https”, localPort = 443, remoteIp = 10.2.1.19, remotePort = 51716, details = "Invalid reference to non-existing object “temp-blob-0” from “new-0"”
2026-07-03T09:29:30Z TRACE HTTP response body (http.response-body) listenerId = “https”, localPort = 443, remoteIp = 10.2.1.19, remotePort = 51716, contents = “{“methodResponses”:[[“error”,{“type”:“unknownMethod”,“description”:“Method Blob/upload requires capability urn:ietf:params:jmap:blob which is not present in the \“using\” property.”},“blob-0”],[“error”,{“type”:“invalidResultReference”,“description”:“Invalid reference to non-existing object \“temp-blob-0\” from \“new-0\””},“set-0”]],“sessionState”:“5ebc9e46”}”, code = 200, size = 360

The user from which I’m trying to create the Sieve Script is Administrator.

Any ideas are appreciated.

Thanks,
Andrei

I understand that topics in this category are triaged by a bot first but a human reply will follow up. If I’d prefer a human-only reply, I’ll add the no-ai tag to my topic.

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2

The error is straightforward: the JMAP request being sent only declares "using":["urn:ietf:params:jmap:core","urn:stalwart:jmap"], but it also calls Blob/upload, which requires the urn:ietf:params:jmap:blob capability to be listed in using. Since it’s missing, Stalwart rejects Blob/upload as an unknown method, and the subsequent SieveScript/set call fails because it references the (never-created) blob.

This isn’t Stalwart’s own WebUI request (Stalwart’s WebUI always includes urn:ietf:params:jmap:blob, along with urn:ietf:params:jmap:sieve, in its using array for every request). The referer in your log (/admin/Account/SieveScript/new) suggests you’re using a third-party front-end (e.g. a cPanel plugin) that’s constructing its own JMAP calls. That client needs to add "urn:ietf:params:jmap:blob" to its using array, and ideally "urn:ietf:params:jmap:sieve" too, since sieve script management also depends on that capability.

If you’re actually using Stalwart’s built-in WebUI at /admin/... and it’s producing this malformed request, that would point to a bug, but the JSON body shown doesn’t match what the current WebUI sends, so it’s worth confirming which client/integration is issuing this request.

This is an automated reply from the Stalwart Help Bot. Other community members may follow up if this answer is incomplete or wrong.

3

I’m using Stalwart WebUI.

Is referer /admin/Account because the user is Administrator.

This is the screenshot of the webpage where I’m trying to create the Sieve script:

image
image1582×897 45.1 KB

4

The same error I encounter if I’m trying from an user without Administrative role:

2026-07-03T09:53:14Z TRACE HTTP request body (http.request-body) listenerId = “https”, localPort = 443, remoteIp = 10.2.1.19, remotePort = 62233, details = [[“host”, “mail.example.ro”], [“connection”, “keep-alive”], [“content-length”, “428”], [“sec-ch-ua-platform”, ““Windows””], [“authorization”, “Bearer sw1.YM2IN-GIoq42gT4Jzl_ReWb8wVLbYj0XPzqEktfYBpX2G4ixwrHzj1j71UI9HVkSNqY.c2lsdml1LnV0YUByZWNlcHRpdi5ybw”], [“user-agent”, “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36”], [“sec-ch-ua”, ““Brave”;v=“149”, “Chromium”;v=“149”, “Not)A;Brand”;v=“24"”], [“content-type”, “application/json”], [“sec-ch-ua-mobile”, “?0”], [“accept”, “/”], [“sec-gpc”, “1”], [“accept-language”, “en-US,en;q=0.6”], [“origin”, “https://mail.example.ro”], [“sec-fetch-site”, “same-origin”], [“sec-fetch-mode”, “cors”], [“sec-fetch-dest”, “empty”], [“referer”, “https://mail.example.ro/account/Account/SieveScript/new”], [“accept-encoding”, “gzip, deflate, br, zstd”]], contents = “{“using”:[“urn:ietf:params:jmap:core”,“urn:stalwart:jmap”],“methodCalls”:[[“Blob/upload”,{“accountId”:“d”,“create”:{“temp-blob-0”:{“data”:[{“data:asText”:“reuire \“fileinto\”;\n\nif address :is \“From\” \“[email protected]\” {\n fileinto \“Trash\”;\n}”}],“type”:“application/octet-stream”}}},“blob-0”],[“SieveScript/set”,{“accountId”:“d”,“create”:{“new-0”:{“blobId”:”#temp-blob-0”,“isActive”:true,“name”:“Forward”}}},“set-0”]]}", size = 428
2026-07-03T09:53:14Z DEBUG Invalid JMAP result reference (jmap.invalid-result-reference) listenerId = “https”, localPort = 443, remoteIp = 10.2.1.19, remotePort = 62233, details = "Invalid reference to non-existing object “temp-blob-0” from “new-0"”
2026-07-03T09:53:14Z TRACE HTTP response body (http.response-body) listenerId = “https”, localPort = 443, remoteIp = 10.2.1.19, remotePort = 62233, contents = “{“methodResponses”:[[“error”,{“type”:“unknownMethod”,“description”:“Method Blob/upload requires capability urn:ietf:params:jmap:blob which is not present in the \“using\” property.”},“blob-0”],[“error”,{“type”:“invalidResultReference”,“description”:“Invalid reference to non-existing object \“temp-blob-0\” from \“new-0\””},“set-0”]],“sessionState”:“5ebc9e46”}”, code = 200, size = 360

As you can see the refferer nou is /account/Account instead of /admin/Account.

5

Update the WebUI to the latest version to fix it.

6

How to update the WebUI? When I’m updating the Stalwart binary WebUI is not embedded?

7

There is an action you can trigger: Action | Stalwart