Vista Keeps Losing Mapped Network Drive due to Account on Domain locking out

OK....one of my coworkers is pulling his hair out of his head. Here's the
problem:

Sony Vaio laptop with Vista business has a mapped network drive.

EVERY time he reboots, the network drive is unavailable. I go to our domain
PDC and I see that his account has been locked. The only I can get the
mapped drive to work is if I sign on using the domain's Admin account.

His local account password matches his domain password, and yet he gets
locked out EVERY time he reboots.

A real pain in the ass!

Any help here would be appreciated!

jlally@ctmbd.com