If you use Outlook in Windows 7 64-bit edition, you may be getting “PDF Preview Handler for Vista” error message when trying to preview PDF attachment right from Outlook. You are still able to open the PDF file by double-clicking it but you just can’t preview it.
If that’s the case, try this:
1. Start Registry Editor.
2. Navigate to HKLM\SOFTWARE\Wow6432Node\Classes\CLSID\{DC6EFB56-9CFA-464D-8880-44885D7DC193}
3. Change the AppID to {534A1E02-D58F-44f0-B58B-36CBED287C7C}
The change takes effect immediately but you might need to close your Outlook and re-open it to make it work.
So what is this {534A1E02-D58F-44f0-B58B-36CBED287C7C} referring to?
It’s the CLSID for 32-bit Preview Handler Surrogate Host that points to
%systemroot%\SysWOW64\prevhost.exe
Another words, it’s a preview handler host used in 64-bit edition to emulate the same function on 32-bit.
Hopefully, it works for you.
