I have created an account, and have shared the calendar to the entire office. Some of the individuals have either been unable to accept the invite as it says "The folder you selected is not available". Some can view the calendar, but are unable to create appointments. Their addresses are set as Editor, but it continues to give this error.

Is there something I am missing?

Hi,

If these users are working in Outlook Cached Mode, please let them switch to Outlook Online Mode to check the result. If the function works fine in Online Mode, removing and re-adding the calendar may help since it seems to be a cache issue.

If the issue persists, could you please detail this scenario a little bit? I've seen Office 365 users used to meet this issue and it was resolved by installing an update:

Outlook 2013 The folder you selected is not available

Regards,

Melon Chen
TechNet Community Su