Hi All,

Working with some colleagues - they are reporting occassional Excel
messages saying "file corrupt" - the files may have started
as .xlsx, .xlt but they were delivered as .xlsm. After editing, by
someone else (various people), they display this message but not
uniformly. The cell data looks intact. The VBA is disabled. Excel has
been set to trust all macros.

Now, I found if I save the file as .xls, close and then re-open, the
VBA modules are now able to run - I used msgbox "hello world" as an
example.

It's not easy to figure out who/why is causing this corruption - do
you have any experience to share and/or tips?