We are attempting to create a branch for parallel developent. We are following the steps in the VSS documentation for creating "Service Pack Projects", as documented here.
After clicking OK in step 15, the recursive share+pin+branch operation starts. It chugs for about 30 seconds, then comes up with the error "File $/Application V 2.1 is already open" where "$/Application V 2.1" is the name of the new project specified in step 12. The error message has OK and Help buttons. OK simply closes the error message and apparently the process has failed since nothing changes, even after a restart of VSS. The Help button on the error message takes me to the Visual Source Safe Online help, where it cannot find a matching help topic.
We've used this process several times in the past and have never received this error message. Today, we've tried the share+pin+branch operation using both the VSS 6.0d client and the VSS 2005 client with the same error.
Full disclosure: we have recently upgraded the VSS clients to VSS 2005, but the server software and database are still in 6.0 format. The server upgrade and maintenance is planned for this weekend, although it's not clear if getting the server software and database upgraded to 2005 will fix this problem or not.
Any ideas about what might cause this error or how we might workaround it

Error: "File $/ShareName is already open" when attempting a share+pin+branch operation
Murbro
We have just had the same problem. We were unable to diagnose the problem specifically but we believe it has something to do with the number of client connections open to the vss database.
Since we were pressed for time, (production server), a reboot of the server fixed the problem.
Had we more time, we would have checked the number of sessions as well as overall connectivity to the machine.