Within Crossware Mail Signature there is a feature to save a "before" and "after" copy of processed emails to help resolve issues.
Save Debug File
To enable logging on the Exchange Server, edit the config.xml configuration file in the installation directory on the Exchange Server, and change the setting below to "Y"
(Default installation directory is C:\Program Files\CrosswareMailSignature)
Check Log folder
The saved copies of the emails are saved in the "log" folder.
The mailsignature.log will show that the files have been saved