Thanks for all the help, Taym. I appreciate it.
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I tried logging in as the user who was having trouble (previously I was logging in as an admin account that currently works on all the systems in the organization). This time I was able to log in successfully. Ugh!
Sure, no problem at all.
Now, if logon was successful, I'm thinking of a faulty ethernet cable/port somewhere between the PC and the Domain Server? Do u think this is possible? If logon worked, there's nothing wrong in the DC/Workstation trust relationship.