[sirka]

Cause: misformed mail signature or misformed html code in received email
Solution: reformat mail signature or remove it (if you are the sender), or
if you are not the sender, either contact the sender or read that message in
your webmail (instead of Outlook) and delete it from there.


In case you want to look for root case, check the mail html source for (most
probably) IMG tags, that are leading to some non-existing or inaccessible
locations, such as shared network folders on someone elses company intranet.