MSBuild Error MSB3071
All drive letters from A: to Z: are currently in use. Since the working directory "'<path>'" is a UNC path, The "Exec" task needs a free drive letter to map the UNC path to. Disconnect from one or more shared resources to free up drive letters, or specify a local working directory before attempting this command again.
All drive letters from A: through Z: are currently in use. Because the specified working directory is a UNC path, the Exec task needs a free drive letter to which to map the UNC path to.
To correct this error
Disconnect from one or more shared resources to free drive letters
Specify a local working directory before attempting this command again.