No long able to share files between machines

Hi all, I have a small network setup running AD on a wink2k3 server. 5
clients, all running WinXP.

As it was an internal test network, every machine simply logged in with the
domain admin account, which was the same as the local admin account on every
machine (yes insecure and silly, but perfect for the internal test network).

However, I have since brought this upto speed, every user now how a seperate
user account, with certain accounts using restricted groups to allow a hand
full of users full admin rights regardless of what machine they are on.

Everything was working fine until I tried to copy a file from 1 machine to
another, if trying to move/copy/create a file over the network now, I get
the error:

unable to create file
access is denied

All of the machines can use the shares on the domain controller but not on
the client machines. I would like any admin to be able todo use shares
across all the machines,

Please help

Taz


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