Google turns up various old threads saying to reinstall IE5 or IE6. The most recent thread I could find is from last month, here."Cannot start Microsoft Outlook. Outlook requires Microsoft Outlook Express 4.01 or greater. You can install Outlook Express by running IE5Setup.exe from the IE 5 folder located on your CD or through the Windows Update website."
The person asking the question said: "There is no IE5 folder on my CD and I can't find Outlook Express at the Windows Update site. Any way to fix this? "
Now, I haven't checked my Office CD for the IE5 folder yet; I'm not entirely sure I can still lay hands on my CD. Although some digging might turn it up, let's assume that my experience will be the same as the questioner and I won't have the folder, either...or, if I do, that it will balk at installing under Win10.
OfficeXP went out of support some years ago, Outlook XP is not fully compatible with Win10, if all was working before (MS Outlook) this would surprise me
OE Was dropped some time ago and is not win10 compatible
You should uninstall OfficeXP, if you can, and if you wish to use MS Office either purchase the latest version, or buy Office 2010 or above from the likes of Amazon
So, can anyone think of a workaround that will get my trusty old Outlook to load again, or do I really have to buy a newer version of Office? I realize that it's 15+ years old and I might just be out of luck...but, as I said, it worked fine until Windows updated a few days ago, so I gotta think there's a way to trick it into running again.