If you did reinstall windows and now the exact same Dolphin build, that has worked before, doesn't work anymore, then i guess you are missing some windows update. If you installed all windows updates, then i don't know what exactly is missing.
The update in question might be:
http://www.microsoft.com/en-us/download/details.aspx?id=36805
The update in question might be:
http://www.microsoft.com/en-us/download/details.aspx?id=36805
