My coworkers have been complaining about receiving email from a certain company without formatting. I see the formatting just fine. Digging in, the differences appear to be that I receive email that contains both plain text and HTML formatting, and the X-MS-TNEF-CORRELATOR header exists but is blank, whereas my coworkers have a value for X-MS-TNEF-CORRELATOR, and a blob of binary stuff at the end which I assume is a winmail.dat or equivalent.
The sender's IT department says they are not responsible for the lack of formatting, but to my knowledge there is no way for these emails to be changed in this way after they've left the sender's mail servers -- in other words, that there's no way for this to be due to my company's mail server (which happens to be Google). Is this correct?
If so, then what can I ask the sender's IT department to look for on what I assume is their Exchange server, which would send email to me in HTML and email to coworkers in MS-TNEF/etc.?