You can try removingall the VSS related files .scc & .vspscc in the Working folder, and then in the .CSProj , removed all the 4 lines
<SccProjectName>...</SccProjectName>
<SccLocalPath>...</SccLocalPath>
<SccAuxPath>...</SccAuxPath>
<SccProvider>...</SccProvider>
Catherine Sea
http://www.scmsoftwareconfigurationmanagement.com/