Hi. I read that the new update was for 'adult' group that got this 'Invalid Page Format'. I wanted to mention that I was still getting this message with
the "DrScience" group.
http://groups.yahoo.com/group/DrScience/
The program was able to get me messages up to May 10th earlier this month, but I can't get any of the messages after that date.
Its a Yahoo issue which they are clearing up server by server. Sadly, you just have to wait.
Until then you should still be able to get your messages if you switch off Message Caching. (File--> Options--> Workflow).
I have PM'd you the location of an up to date archive file.
Cheers,
Wilson.