Hi Vijay,
Thanks for using Syncfusion Products.
We are unable to reproduce the issues reported by you and the Postback controls on the page are working fine in our end after export to excel. We have prepared the simple sample to demonstrate this and the same can be downloaded from the below link.
ExcelExport-78297311.zipPlease have a look at the above sample and if still the issue exist, could you please try reproducing it in the above sample and give it back to us so that we can look into it and suggest a solution quickly?
Please let me know if you have any concerns.
Regards,
Bala Murugan A.S