Mail Attachment Error in Horde

[PixyPumpkin]

Mail Attachment Error in Horde (IMP)

- Customer receives a mail on webmail.domain.nl
- The mail has a JPG (photo) attachment of 11MB
- The mail can be openen (display) but doesn’t show
- The attachment can NOT be saved
- The mail can be forwarded
- A seccond mail of 9MB (.ZIP) does not have problems

What could be the problem?
Is it the .JPG or is it the size of the mail?

 

[eWebtricity]

I would guess the size of the attachment, that's pretty big for email.