Error copying Steam New update

Hello,
I am using Windows 7 Ultimate and have noticed that steam will no longer open after steams latest update of july31st, 2012. How can I fix this issue to resolve the following issue? Any suggestion would be really helpful to me.
Thanks in advance.

Error:
Steam.exe(main exception): ERROR: copying SteamNew.exe to Steam.exe failed, Win32 Error 32 "The process cannot access the file because it is being used by another process."
