I was directed to this forum from the SharePoint Answers Community.
We are using SharePoint on premise and have a SP calendar site that is no longer able to sync with new users because that site has more than 5000 records with about six years of calendar items. Existing users have not experienced any change to access or usability.
I have updated the default view to select the prior 4 years of entries so the count of items would always be less than 5000 going forward.
However, new users are still not allowed to be sync'd with their outlook because the returned list is still more than 5000 when the attempt to sync is done. Also to my knowledge the employees that need to sync with outlook have and are using their O365 accounts.
Our IT staff has informed me that through their research, the Outlook sync doesn't look at the SP default view. This doesn't make any sense to me because that would imply a gap in functionality which in theory would break SP once the number of records was larger than 10,000 (for SP 2019)!
Any suggestions to help me resolve this syncing problem would be appreciated!
Thank you!


