Hi Aditi,
Thank you for posting your query to us.
I am afraid that i was not able to reproduce the issue in your sample. Also i have created a simple sample that implements the IBindList collection with 9 unbound columns in a grid to test this issue and it is available in the following link,.
EntityCollectionSample.zipPlease have a look at the above sample and if still the issue exists, could you please try reproducing it in the above sample or send us the reproducing steps that we could sort out the cause of the issue and provide you a solution?
See this KB article for adding the unbound column in a grid.
How do I have an unbound checkbox column in a GridGroupingControl?Best regards,
Haneef