You have tried to select too many rows error when selecting many items in a folder in OWA
Original KB number: 2394261
Symptoms
When you use OWA for Exchange Server 2010 SP1 and try to select a large number of items in a folder, you receive the following error:
You've tried to select too many rows. Select fewer rows and try again.
Cause
This behavior is by design.
Resolution
Select a maximum of 40 items in a folder for any actions required, such as Copy To Folder or Move operations.
More information
This problem does not occur in the original release version of Exchange Server 2010.
Microsoft regularly releases software updates to address specific problems. If Microsoft releases a software update to resolve this problem, this article will be updated with additional information.