Hello Marin,
Thanks for reply and it is very descriptive.
As issue concerns, RaisePostBackEvent is stating for Telerik.web.UI...Name space i don't see the cause to happen it in ASP.net or share point framework.
Anyway's, as per your suggestion, I will try to incorporate Raisepostbackevent for page and see.
More over, we are handling filtering/Sorting and paging through SQL for that we are using custom paging option with GRID. at a time we will bring only 10/20/50 records based page size and retrieving virtual count property of the grid to hack page count/numbers.
As described earlier post, the event is not hitting server (pageload) it is returning from browser it self and it is very quick when this error is occurring, and it is likely to happen after few click on pagenumbers/sorting (once per average 10 clicks). and error is occurring only in higher environments (stage and production), dev environment working very smooth with out any issues.
Please help if this additional information help to narrow down actual cause of the error.
Thanks for your time.