Vista - New User - Logon Fails

I am the only user of a standalone PC running Vista Home Premium.
There is only one account set up (mine). I am Administrator. I have turned
off Guest Account long ago.
I attempted to set up a Standard account for my wife so that she can
download and view her digital photos without fear of her changing any other
settings. I used Control Panel / User Accounts / Manage Other Accounts / Add
Account
Although the account appears to be set up OK at this point, when I log off
as myself and try to logon as my wife, or reboot and attempt to sign in as my
wife, I get the message "User Profile Service Failed at Logon" - "Logon
Denied".
I can still log on OK as myself - Administator.

I have deleted my wife's account and added it again a couple of times, still
no good. I have turned Guest account on & off, this doesn't affect it either.

I have turned User Account Control On & Off; again still no luck.

I really do need your helpful ideas please.

Thanks in advance