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I've recently upgraded to Ubuntu 12.04 and so far I didn't have problems with it. Until I decided to make a stupid mistake of messing with the Compiz settings and making the GUI disappear. I made some research and I managed to get it working again, but I felt like it was still partially broken, and Unity became slower than before.
I didn't bother with this anymore, found out the Compiz/GTK/Unity settings are separated for each user, so I logged in as guest, deleted my main account and created a new one.
There's one problem though. When I created the new administrator account, it didn't ask me for a password, but when I tried to log in, it asks for a password and now I have no idea on how to set/change the password for this account, since I can only login as guest without superuser/root access.
I use this PC for development, although I'm a total noob with Linux. I would appreciate if someone knows a way to change the password rather than having to reinstall 12.04 from scratch.