For several months now Win2000 DUN will run fine for a time -- a day or a week (it seems to vary) -- and then suddenly forgets how to connect to the internet. "username or password invalid on domain" messages pop up. It is not at the ISP level. A second computer will connect no problem. The only cure, at the moment, appears to be to delete the connectoid, and set up a new one with exactly the same settings. This generally clears the problem immediately. I haven't been able to tell if the problem happens after a certain number of connections. But I am frustrated. ... A reboot doesn't help. (At the moment I am using SP4, although this began before that was installed.) ... Has anyone any clues?