She thinks it started when I got AVG, which somebody else installed, finally working (before I came automatic updates were broken due to an occasional Vista AVG installation problem). But she's not sure. The problem is that a few senders' emails show up as plain text, not HTML. Most HTML emails show up fine, including all that I and other people in her office send (as in everything I can troubleshoot myself). She thinks all the emails showing up as plain text are coming from macs. And she has a stupid HTML signature that she wants to show up as HTML, and of course you can't force Outlook to use HTML to respond to plain text emails.

I uninstalled AVG and installed Avast today - same problem. No idea what else to do, I think its probably on the sender's end but I have no fucking clue. Any ideas?

Every frickin link I find mentions AVG, but I uninstalled and made sure to remove all user settings and other shite. So unless Avast causes the exact same problem, this is very annoying. Don't suppose you have ever seen this before?