This is not a question, it just an informational post to save someone with a similar problem a little time.

I have a document managment application that uses an OLE control to preview scanned images, usually PDF and TIF files. After upgrading to Adobe Reader 10 today I started getting an error "OLE error code 0x80004001: Not implemented" on an APPEND GENERAL command that loaded the PDF file into a general field for use by the OLE control. TIF and other file types still worked fine. A work around to get past the error is:

Open your Acrobat, got to EDIT - PREFERENCES - GENERAL - and uncheck the box for "Enable Protected Mode".
(That checkbox is near the bottom of the screen.)

The credit for that workaround is to this posting.
http://www.access-programmers.co.uk/forums/showthread.php?t=205928