Scenario
You are using Exclaimer, and you notice that the emails with large attachments do not have a Server-Side signature appended to them.
Reason
To ensure that all emails are processed efficiently, it is necessary to impose a limit on the email size to which Exclaimer will add a Server-Side signature.
During transport, emails undergo some level of decompression, and emails can increase in size by up to 30%, depending on the content of the email. In worst-case scenarios, signatures may not be applied to emails having around 24MB (at the time of sending).
Resolution
We recommend applying Client-Side signatures to emails with large attachments.