To create an event, certain mandatory fields must be filled.
When adding an event directly in Outlook Calendar, missing key details isn’t an issue—you wouldn’t create an event without a date, right? However, when using an integration, required fields might sometimes be left empty, preventing the event from being created.
What are Outlook Calendar mandatory fields?
The only required field for creating an event is a date.
If other fields are missing, default values will be used. You can see the defaults here -Events Dates & Hours.
Troubleshooting
Check your field mapping – Ensure that in your mapping the correct column is mapped to the required fields (Fields Mapping)
Verify the mapped column has a value – For example, if you mapped a Date column, make sure it actually contains a date.
I re-assigned an event and the previous one wasn't deleted
When using the personal calendar, Events don’t move between calendars – If an item was initially linked to Person X’s calendar and later assigned to Person Y, a new event is created in Y’s calendar, but the event in X’s calendar remains and they will need to manually remove it.
For teams where events frequently move between members, we recommend using the Team Calendar, which allows for smoother reassignment and event management. See here ->