Hi Tejaswini,
At first, I agree to John Chen MS: we need to check which part of your code costs too much time or cause the low performance. You can use a DateTime variable to trace the executing time.
Second, could you please let me know how many records are loaded to the DataGridView. If the DataGridView contains too many rows, the performance would be very low. You can implement the virtual mode to improve the performance. This is a walkthrough:
http://msdn.microsoft.com/en-us/library/2b177d6d.aspx.
Let me know if this does not help.
Aland Li
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