I have never been able to log onto windows 98 after I installed it. So what I do is I turn on the computer, it goes to the username and password enter screen. I type in everything correctly, and that disappears. Then another window pops up that says "Updating System Settings". That shows for a few seconds, the screen goes black, and the computer restarts, reloads, and returns to the username and password screen. Can someone tell me what is going on?

You seem to be in a startup loop. Can you boot into Safe Mode? (Tap the F8 key during a boot to get the Windows Startup Menu. Choose Safe Mode.)

If you can, check Device Manager for any errors with the hardware. Then run the System File Checker (SFC). Start, Run, type in sfc and hit ENTER. Have your 98 CD handy.

in window 98 you can log in without correct username , password because win 98 does not provide security this is problem related to startup options .

run your computer in safe mode. by pressing f8 key during starting