When sending an email in webmail, the operation fails with the following error message:
SMTP Error: Message size exceeds server limit
Emails with large attachments (more than 10 MB) are not received. The sender receives the following email message about failed email delivery:
552 5.3.4 Message size exceeds fixed limit
The following error message may appear in
warning: queue file size limit exceeded
The size of the email exceeds the limit configured in Plesk at Tools & Settings > Mail Server Settings > Maximum message size.
Go to Tools & Settings > Mail Server Settings.
Increase the Maximum message size value.
Click OK to apply the changes.