A family of Microsoft word processing software products for creating web, email, and print documents.
There are three steps to solving this problem. You can probably do them yourself, or you may want to have your tech do it.
- Use the Windows System Restore process to roll back to the system state from before the update occurred.
- Open the Windows Update program and click Change Settings on the left side. On the next page, change the first dropdown from "Install updates automatically" to "Download updates but let me choose whether to install them". Of course, Microsoft wants you to let all updates be installed automatically, but there are enough dumb mistakes like this failure to install the Validation Add-In correctly to make that bad policy.
- You can immediately run a new check for updates, or just wait until you're notified that some are available. Look at the list of proposed updates. If you see the Validation Add-In there, right-click it and click Hide Update. That will prevent the update from being installed, now and in the future. Be aware, though, that Microsoft could release an update with a different number that would also try to install the add-in, and you'd have to hide that one too.
The Office File Validation Add-In is not a critical or necessary part of Office. It's intended to keep you safe from malicious binary-format files (more info here), but such files are rare and becoming rarer. Just be suspicious of .doc and .xls files that arrive from outside your company, if any do.