Why won't Ubuntu installed using Wubi accept my password?

I can boot into Ubuntu just fine as a guest but it refuses to accept my login name and password that were set during the Wubi install. I reinstalled it again with basic login and password just to make sure and it still won't let me in.

There have been some reports of this. It's not clear what the cause is, but you can try resetting the password as follows:

1. After selecting Ubuntu hold down the Shift key until the Grub menu appears. If you're using Windows 8, the computer will restart - in this case as soon as the BIOS screen disappears hold down then Shift key.
2. Select the second entry, Advanced Options.
3. Again, select the second entry for Recovery mode. It will boot to a recovery menu.
4. Select Remount drives as read/write
5. Select Root shell

6. Check your username by entering:

   ls /home

7. Reset your password (replacing with your Ubuntu username which you saw under /home):

   passwd <username>

8. Enter exit to leave the shell and then select Resume normal boot

e.g.

root@ubuntu:~# ls /home
bcbc
root@ubuntu:~# passwd bcbc
Enter new UNIX password:
Retype new UNIX password: