Try this - it worked for me on 64 bit Win 7.
I did manual regedit, didn't even close outlook or reader, performed edit, then went back a few minutes later and opened a new email and preview worked.
Thanks Mike, that almost worked. It seems that new emails I receive with PDF attachments can be previewed no problem but pre-existing emails with PDF attachments cannot be. Does that make any sense?
Do you know a solution for Win XP - Outlook 2007 and the Preview Pane error?
I have the same problem but on a 32 bit system.
After install of adobe, make certain you have run the Adobe Reader from the Start Menu. It appears to need to do some configuration the first time the product is run. This needs doing even if you have right clicked on a pdf attachment and opened it.