I have received your answer, but, I just can Closed it, because, there's no Reply button there. So, I create new thread to thank for your supportation and submit new bug, I think this is a bug.
The scenario likes this:
Update panel named UpdatePanel1 contains a RadScheduler named RadScheduler1.
Button1 is outside UpdatePanel1 and be trigged as AsyncPostBack from UpdatePanel1, when click, make RadScheduler1 change to AdvanceInsert mode
Button2 is outside all, and inside UpdatePanel2.
Run project as debug, set break point within RadScheduler1_FormCreated.
Click Button1, after AdvanceInsert form apprear, click Button2. You will be brought to FormCreated event of RadScheduler1.
This will make your application reload many times if there some load data event attach to FormCreated event, and make application run VERY SLOWLY.
I can't attach example to this thread, but everyone can download it from here: http://www.mediafire.com/download.php?zxrt2tijgul