I still can't find my missing sheets with the above suggestions....
When I start up the Particular book I am working on, I momentarily see the tabs before they disappear, so at least I know they are somewhere.
Also, if I start up a blank book, the sheet tabs are there no problem, so I know I don't have to reinstall Excel.
But I still have to recover the sheets that are missing - would anyone have any other suggestions as to how to retrieve them?
TIA