You are trying to setup a "Throttling Window" under the "Software Delivery" tab for one of your "Targeted Agent Settings" policies (under Settings > All Settings > Agents/Plug-ins > Symantec Management Agent > Settings > Targeted Agent Settings).
In this example, the below image shows that there are 2 Throttling Windows, which one is set from 2:00am with duration of 6 hours, and the second one has the start time of 8:00am.
However, when you try to save it, it gives error:
Software Delivery: Overlapped time windows are specified. Please correct problematic throttling periods..
ITMS 8.x
Overlapping schedules are not allowed. Even when you have a schedule that ends at 8am and another that starts as 8am may cause this issue as well.
Define the times so there will be no overlap.
Now from 02:00 to 8:00:59 will be 90% and from 8:01:00 to 10:01:59 will be 5%