I have this monster file that needs to be accessed by multiple people so I
set it up as a shared file, however periodically when the file is opened
there will be several tabs missing. The file is used monthly and each month
is saved as it's own file and most of the sheets in each file are used,
sometimes the missing files have been updated already which means when it
disappears the work has to be re-done. Everyone claims it's not user error
but I can't find a reason why excel would just randomly delete sheets in the
file.

Any ideas????

Thanks!