You are looking at the wrong id's with MFCMAPI. Seeing as this is a Memo/Notes issue you need to lookat the PR_IPM_NOTE_ENTRYID in the Root Container and the PR_ENTRYID/PR_MEMBER_ENTRYID in the Root Container/Top of Information Store/Notes directory.

If these are different you can try running outlook.exe /resetfolders to correct it. If that fails use MFCMAPI to update the id in the Notes folder. But be warned, this is at your own risk.

Just copy the id's into a txt file and label their directory so you can put them back.

The last step is to either rebuild the mailbox or create a new one.

Let us know how it goes.