Files attached in tickets are not being sent, but we do receive clients attachments

[cuenta0gow]

Version: WHCMS 8.12.0

Type of license: Plus

 

The files we attach in our tickets won't send, despite of being uploaded. We press the "Attach Files" button, choose any file then we send. The mail is received without the attachment.

We already checked all users permissions to determine that is not the problem. We are aware there are some allowed file extensions and the max file size limit, we respect those and attachments still not sending.

We gave all permissions to "attachments" and "downloads" directories in WHMCS document root to prove is not a permissions issue, but it didn't work.

There is nothing in system logs that tells us if there is something wrong.

We already checked every setting in Configuration and everything looks enabled.

When clients send us emails files are attached correctly . 

 

Do you know what is causing our issue? Any help would be appreciated, thanks in advance!

If you need us to provide anything information, just let us know please. 

[cuenta0gow]

We didn't mention that we don't get any error message when attaching/sending.