It's never happened to me. As far as I know, PC keeps track of your logged-in status through a cookie on your computer. I wouldn't think you'd be able to log in at all if your browser weren't set to accept cookies. If something were clearing your cookies during the session, though, that would probably cause symptoms like the ones you're describing.

Do you have a choice of more than one browser? If so, does this only happen with one in particular?

I'd want to check my browser privacy and/or security settings, especially the ones relating to cookies, and any anti-virus or anti-spyware programs that I had running in the background.

If none of that turned up anything and I felt like troubleshooting some more, here's what I might try (longish story ):

Before I ever got online myself, a friend did. She was a bit paranoid about the idea of letting websites leave these things called cookies on her computer and explained her reasons to me, sort of -- basically, "How dare they?" When I got connected a few months later, naturally I wanted to learn more about cookies first thing and see how far I could get without them. I looked at the available settings on my browser and chose one that would have the browser ask my permission before accepting each cookie. Then a-browsing I did go.

I soon learned that some sites were setting no cookies, some were setting half a dozen or a dozen (these I started steering clear of), and some where I had to log in were regularly setting the same two or three each time I logged in. That was how I first found out that logging into a website had something to do with cookies. I was thinking you might want to set your browser to ask you every time it sets a cookie, and see if you learn anything that way. For instance, if it didn't ask to set a cookie when you logged into PC, that by itself might suggest that something wasn't working right.

Something else you might want to try would be logging out, clearing your "private data" (meaning history, cache and cookies I guess), and starting over with a clean slate.

For me, the "Remember me" setting makes no difference during a session; with the box checked or unchecked, I go from PC page to PC page without a hitch. The difference comes at two points:

-- If I close my browser and maybe turn off my computer, next time I go to a PC page I'll find myself reading as "Guest". If I click a link or bookmark to a page that requires me to be logged in, the forum software will deny me access and ask me to log in first.

-- If I take over an hour to write a post or PM and don't preview (or click on any other pages) in the meantime, the software will decide I must've left and quietly log me out. Then, when I do click "Preview" or "Submit" it'll find I'm not logged in and sometimes give me a hard time. This rarely happens to me because I usually do keep the box checked, but at least once I've come close to losing a post.

Just going from page to page, though, the "Remember me" setting shouldn't make any difference and you shouldn't be getting logged out like that. Do let us know what you find out.