Your message is just another confirmation of the two golden rules about general fields:
Rule #1: Avoid general fields, at all cost. Use separate files instead.
Rule #2: If you absolutely must use a general field, see rule #1.

>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