Credentials supplied conflict with an existing set of credentials
This is not directly Delphi related but happens sometimes when setting up shared drives. In my case, I got this error message after installing SAMBA on a Linux box, then sharing a directory and the protecting this resource on the Linux side with an account.
I tried to access the shared resource from a Windows NT machine via Explorer or command line using NET USE - but kept getting this error message:
'Credentials supplied conflict with an existing set of credentials'
(On a Windows XP box this error did not occur.)
From Microsoft: 'Windows NT does not allow you to make multiple connections to a shared network server from the same workstation if you attempt to use more than one set of credentials.'
This was basically a long winded version of the error message. Not too helpful. I looked at my shares but could not see any mapped drives to that machine except the IPC entry.
At the command line, in a desperate attempt, I removed all shares to other machines with this trick:
NET USE * /DELETE
It was an attempt because until now I didn't realize that the NET command accepts wildcards (*) for machine names.
After that I could connect just fine. I suppose booting the machine would have done the trick as well.
Another possiblity is to provide the TCP/IP address of the computer instead of the computer name when you make that second connection. If you were already using the IP number in the first place, try the machine name this time. That might save you from removing all your network shares.