The dear folks at Microsoft have told me that the error message - dwwin.exe DLL Failed to Initialise -is caused by my Comodo Anti-virus (Beta 2.0) software.
If you're using CAVS, and MS says that's the issue, you may want to check the HIPS Block list for dwwin.exe (you may have inadvertently blocked it).
Open CAVS, and go to Settings/HIPS/General. Look for the Manage Allow/Block List. See if there's a block entry for dwwin.exe; if so, remove it, or change to Allow.
LM
PS: On the basis that MS says CAVS is to blame, I'm moving the thread to the CAVS' side of the forum.