Interesting thing we learned today, if the files are not on the same domain as the computer, for example computer is joined to acme.local and the file shares are on acme.local the error goes away since it’s a trusted location per the defaults in excel.
When pulling the file off another server, for example acme2.local and this server does have a trust relationship and we got the pink error. We migrated most of the files over today and haven’t had any calls except someone messing with macro settings, but that’s it. Sending a few emails and updating our GPO desktop shortcuts to the files fixed the mess, with a few reboots, Not saying this is the fix, but just sharing our experience.
Microsoft azure support and office 365 support were no help, all they told me from
Both depts is to run some Group Policies to block this. Even going the manual way of following the scripts those didn’t work.
Microsoft better have a patch soon, I’m still not sure what update on the pc’s or server caused it.