Windows 7 home premium 32bit - won't accept user password after update

I recently installed Windows 7 home premium 32bit on my Dell XPS 400, which was previously running XP. I downloaded the iso file and copied it to an external drive, and the installation went fine. I set up a user name and password, which I used several times, but the other day there were a large number of updates, and now it won't recognize my password, which I'm sure I'm entering correctly. I've looked at some tutorials on how to reset it, and downloaded a reset program, but haven't been able to make it work. I don't really know what I'm doing, so I'm afraid to get in over my head. I have a laptop with Windows 10 which I use most often, so I can use it to create a bootable disk or usb drive. Any simple advice would be appreciated.

Does it say "wrong password" or "profile not found"
A friend came to me with a laptop and the problem was with the profile file where the password is stored.
In that case, there was no password to reset. Had to do a different approach.