Hmm. Was the 'correct' one exact same as the 'corrupt' one before adding the disclaimer? Looking at them the good one has base64 MIME for the attachment & the bad one doesn't look corrupt but is plain text & missing attachment entirely.
Also I noticed the PDF is one of those 'text'-looking ones that seem to get encoded wrong sometimes & wonder if that is coming into play here.. Since you have an older build of hmail perhaps updating to latest might solve it if the corruption is happening during POP3 download. Here is changelog:http://www.hmailserver.com/?page=change ... sion=5.3.3
Issue 312: In some cases, the POP3 server returned incorrect data which could lead to corrupt attachments. Changes have been made to prevent this error. The error was apparent when retrieving PDF files which had been sent using Outlook Express.http://hmailserver.com/issues/?312
If not that issue perhaps hmail is mucking up the MIME when adding the disclaimer in the script so I'll play with your email myself when I get a chance.
Also, are you sure GMX Antivirus/antispam doesn't have a hand in it? Worth disabling to test because you never know.
Thanks for following up with the messages!