>Looks like when I copied the command "sn -k keyPair.snk" from the webpage it included some hidden special character and hence not working. when i typed the command it worked. It created the new DLLs, but still it gives me error! I am still working on this. may be something to do with the assemly cache.

When I had a very similar problem it was because I still had the old dll files in the bin folder. I also once had to delete an old dll from the GAC as well. Worth double checking those things.
Good luck
Tim