Windows System Error

When I dail up to the Internet, I get an error that say's
the following: system error, a duplicate name exists on
the network! I don't get this error until after my
connection has been completed, and as soon as it is I get
that little yellow warning icon in my task bar, and it
sates that abovementioned error. I have recently put a
new hard drive in my computer, formatted it and
reinstalled my OS, my computer has never ran better, but
I used to get this error even before I did. If anyone
can help me out I would really appreciate it.

I've looked everywhere, and I just don't know where the
settings are to eliminate the problem. I only have one
connection on my computer, and that is my one and only
dial up configuration. Help Please!!!!!!!!!!

Thanks,
Matthew
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