Which worked for us and is much simpler, does not require manual editing of the registry / file, and I'm sure it is safe:
1) Exit completely from Visual Studio.
2) Disconnect from the network (disconnect the cable and turn off the wireless network or disconnect the network adapters)
3) Open the VS6 workspace (DSW) for the project. When it starts, it will discover that it cannot connect to the VSS database that it wants and ask you about it ...
4) Tell VS to never try to reconnect to the original db control unit in the future.
5) Done ... VS makes all the changes to the THAT WORKSPACE / PROJECT setting for you. You do not disconnect VS from the source control at all (for example, editing the registry) and your files are not manually edited.
Minok
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