Update this AM at 9 AM removed from my computer all of pics, music and documents. I am 72 and not happy!
All of my down loads were deleted, my programs of Excell & publisher, all of my music and I-tunes program!
That definitely should not happen! All of the changes made by the update should be in Mozilla-specific folders and not affect other programs or their files.
Have you tried a normal shutdown and restart of Windows 10 since this happened?
If you try a search in the Windows search box (on the Taskbar or Start menu) for excel does it give you a link to the Excel app?