Doh!!! Still doesn't seem to work from home, although that cookie-killer app is a wonderful thing, Jafo! I've checked the internet settings on the computer to make sure that cookies were fully enabled, thinking that would permit me access to entering messages, but still not working. It's really strange! I've emptied out the temporary internet files folders, and erased any cookies encountered and retried logging in.
When I log back in, everything looks like it should (my selected wincustomize theme comes up, and it still says "Welcome Mr. mrbiotech"), but entering a message brings me to a warning screen (You've attempted to enter a members-only area...). When I log back in and select "go back to the last screen" it brings me right back to the warning. I'll try twiddling with the internet settings some more and see if my recent upgrade to Win2000 altered anything.
Thank you for your help, guys!