We have a hybrid set up with around 65% of users now Exchange online, the remainder being migrated over the next few weeks.
A problem has cropped up that I am struggling to find a solution for. A resource calendar still hosted on premises, gives migrated Outlook users an error when they try to view events. The error reads:
"You do not have permission to view this calendar.
Do you want to ask <resource mailbox name> to share his or her calendar with you?"
If you say yes you can open the item and view the details.
Searches for this issue all seem to say log into the account and give access to the calendar. 2 issues with this:
1.you can't add access that way if the user you are adding is 'non-local'
2. Adding hundreds of users? Not an option
Some "solutions" say this only affects Outlook, which is kind of true. OWA does not give an error, it simply doesn't open the events, no error but no access to the events though you can see the subject and location
Is there any alternative solution to this?