Issue Description When trying to sens an email to user+test@mydomain.com , it says that mailbox doesn’t exist bud subaddressind is enabled for mydomain.com Expected Behavior The email should be accept and delivered Actual Behavior The email is refused with code 550 (5.5.0) ‘Mailbox not found.’) Re…

There are two separate issues at play here, and fixing both is required for subaddress delivery to work. 1. The subAddressing setting on your Domain must be enabled. Subaddressing is not controlled by your SQL queries – it is configured per-domain on the Domain object via the subAddressing field.…

Thanks for that explanation, but subaddressing is enabled for the domain and problem is still there.

Let me look more carefully at how subaddressing interacts with the SQL recipient query. The core problem is almost certainly your queryRecipient SQL. Let’s look carefully at what you have: SELECT email FROM stal_emails WHERE $1 like (emails) This has the operands backwards. SQL LIKE syntax is col…

I carefully followed your instructions. Mails sent to user@mydomain.com are accepted, but same error persist when sent to user+test@mydomain.com Are you sure that the pattern +test is not present in $1 for the SQL query ?

This is the key. The source code tells us exactly what happens. Let me look at the split logic more carefully: In the code at line 65-66: } else if let Some((new_local_part, _)) = rcpt.split_once('+') { local_part = Cow::Borrowed(new_local_part); Note it uses rcpt.split_once('+'), not local_p…

So I checked my sql queries on the database server and everything works fine there. I also restarted stalwart server and invalidate all caches in webui to be sure. I also make check trough the webui with Delivery tests. If I test address user+test@mydomain.com , it says “Recipient accepted”. If I t…

Please check your SQL server logs to see which queries are being done when an email is received. Alternatively try using the internal directory to test subaddressing and once you have it running enable your SQL directory again.

This is very revealing. I can now see what’s happening clearly. The source code at get_directory_for_cached_domain shows a critical difference between Community Edition and Enterprise Edition: Enterprise Edition: uses the directoryId linked to the specific domain for recipient lookups. Community …

I got an Enterprise Edition so your answer is not relevant here. Or the problem is the same with both Editions.

Looking at the Enterprise Edition path in get_directory_for_cached_domain: return domain .id_directory .and_then(|domain_id| self.core.storage.directories.get(&domain_id)) .or_else(|| self.get_default_directory()); For Enterprise Edition, it uses the directory linked to the domain via d…

Subaddress and sql directory

Issues

palight June 3, 2026, 9:45pm 18

Hi, for memory, I just post the link to my last discoveries with trace log enable. Seems that issue is general with external directories.

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Subaddress and sql directory

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