This can happen depending on the mailstructure if the attachment has some unrecognized structure.
Best would be to save your mailfile as a raw RFC .msg format (.eml), set this as $debug_file inside the popfetcher class and analyze the debug output. I can try that if you can provide me with such an email that doesn't work for you, then I'll try to reproduce your current settings.
Regards,
Garvin
# Garvin Hicking (s9y Developer)
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It seems, the option "remove html..." also removes the img-tags from content, if submitted e-mail is a simple text-mail. I have deactivated this option and now images are included into entry-body.