I’m talking about the SharePoint 2010 calendar list validations in this post.
Well, what i mean by ‘Past booking’ is user should not be able to add an event in the past date/time and Limit Advance booking means user should not be able to add an event beyond a limited number of days (eg: 2 days)
Calendar > List Settings > Validation settings > Formula
The below formula will prevent the user from booking for the past date/time.
If you don’t want the user to created an event beyond 2 days limit:
Now, what if i want to combine both the above validations!! Here it is:
=AND([Start Time]>Created,[End Time]<(Created+2))
With this above formula in place, user won’t be able to create an event in the past date/time neither will he be able to create an event beyond 2 days from the current date/time.
Few more reference links for list/column validation: