Cannot access XP network share from Vista machine

[SinaiSound]

I'm tearing my hair out trying to figure out this problem

I'm trying to connect to my XP machine in the front room from my vista machine in my bedroom.

The vista machine can see the xp machine in networks, but everytime I enter the username and password, it tells me that the logon was unsuccessful

The administrator account on each machine both has the same password.

Any ideas

 

[SinaiSound]

Thanks for the tips so far guys.

The annoying thing, is that it was working a few weeks ago

I'm going to disable the account password for the administrator on the XP machine to see if that has an effect. Not an ideal solution though as I remote desktop into that machine, so I need a password; although I could create a seperate account with a password for doing that.