Hello
i installed ubuntu via wubi but my widows got corrupted and had to be restored i wanted to restore wubi so i reinsatlled wubi and replaced the new root.disk with the old one but the issue i am facing is that it asks for a login password at the root screen which i am sure is being entered correctly but it says login incorrect
however after replacing the same root image with the new one its working absolutely fine kindly help me restore my original installation
thanks in advance

ubuntu version 11.04
however i must imform that the linux image of my new installtion differs from old one is this creating the issue if so kindly help me replace the linux image as well