Anyone have any tips I might be able to have this user try?

I'm running Threads 7.5.4.2

Here is what he is reporting:

Quote
HI, I got a new PC at work and it has windows 7 and IE8. I am having trouble staying logged in. I went to FAQ's and saw that I need to allow cookies (which I did), but still having issues. I log in, then when I click on any other thread, it tells me I am no longer logged in. Any suggestions? thanks