Scenario:
If a user tries to book a time off for 4 hours on 25th August. The user selects 25th August for both start and end dates and in the partial day off field type 4, select the start time as 1:00 PM. When the timeoff booking is submitted, the following error is shown Error: Start Date partial day hours cannot be empty and must be less than or equal to 0.1 hours. (Please check the attached screenshot)

Cause:
The issue happens because of incorrect value entered under Hours per day setting in the user profile. In the above example the hours per day was set to 0.1 hours. So if the hours per day value is lesser than the Timeoff requested the above error is shown.

Solution:
Make sure the hours per day value entered in the user profile is correct. Mostly hours per day is set to 8 or 9 hours and whenever someone request a TimeOff it will be for this value or fraction of it.

Note:
This error message is shown when submitting a Time Off for a partial day.