Thank you. That's just it. It simply doesn't work. No error message or anything. When I click on "Find and Replace," nothing at all happens. Control-H doesn't work, and neither does the "Go To" function. I have restarted Word and rebooted the computer
as well. "Find and Replace" came back, but since I've had this issue for years - and I don't want to be negative - but it always happens again and is entirely frustrating since I'm paying monthly for the service and not getting the service I need. As a writer
and editor, I can't underscore the importance of "Find and Replace" and I use it in probably all documents that I edit. I've even uninstalled Word entirely, only to have "Find and Replace" quit working again.
OK, so the Ctrl+H shortcut does not respond, sometimes. This could be caused by some sort of add-in, but I have no idea which one, because I have never seen the issue myself. Steps to troubleshoot add-ins can be found in the article at
https://docs.microsoft.com/en-us/office/troubleshoot/word/issues-when-start-or-use-word.
Another possibility is that some other program on your computer has "hi-jacked" Ctrl+H. I suggest that you try assigning a different shortcut to the
EditReplace command, via the Customize Keyboard dialog box (File > Options > Customize Ribbon > Customize).