Specifying what to open a PDF with from an OLE field.

Here's an interesting one that is driving me insane.

Access2003 with Windows XP.

I have a direct scan and save function that enables the user to press a button which scans a document, converts it to PDF and saves the result in an ole field. When the user opens the PDF from the ole field the document opens fine in Acrobat Reader, but when the user closes down the file, the following message appears.

"The operation on the Acrobat document failed.
The OLE server may not be registered.
To register the OLE server, reinstall it."

It has no effect on the document or the application and the user is able to reopen the document at will without a problem. But each time the document is closed, the error above appears.

There are two real questions here.

1. Has anyone experienced this problem or know why it is happening?
2. Rather than open the ole field in Acrobat reader, is there any way I can get the ole field activation to use Internet Explorer to view the PDF instead?

Many thanks