I am running SP Server 2013 with the Dec CU on my internal farm. This past week, I migrated 1 database containing 1 site collection (also ran the site upgrade to 2013). Prior to the migration, the users were using Datasheet View in 2010 to bulk edit and also add attachments through the pop up window while in Datasheet View. After the migration, performance on their list using IE8 with less than 300 items was horrible for the end user and also for me as a farm admin (I'm running iE11). I created a new view and performance seemed better for me and a slight improvement for the end user, but still not satisfying. The end user is using Chrome in the interim until I can test with IE9 to see if that makes a difference.

My main concern is the Quick Edit view. This user needs to be able to use the 2010 Datasheet View to manage attachments while in DS view. I created a new DS view on the affected list, but it still defaults back to the Quick Edit view. This list is on 1 of 3 web apps in my internal farm. The interesting thing is that I can create a 2010 Datasheet View in a custom list on a site that was created in 2013 from scratch in another web app on my internal farm. However, I can only do this on 1 of 3 web apps. On my 2013 external farm, I can create a DS view in a 2013 site created from scratch in 1 of 2 web apps. Creating a list on the 2nd web app in DS view defaults the list back to Quick Edit. I checked in SharePoint Manager thinking there was a web app feature that wasn't getting activated. There was only 1 web app feature that jumped out. Academic Library Site Safe Controls was activated on the 2 web apps I could create the 2010 Datasheet View on, but not the other 3 web apps I could only seem to get the Quick Edit view when creating the DS view.

Is there a feature that needs to get activated or one that might need to be deactivated/reactivated? My internal farm with the 3 web apps is running the Dec 2013 CU and the external farm w/the 2 web apps is running the March 2013 PU.

Aside from that, I've received complaints on the list performance using IE and not being able to use the 2010 datasheet functionality as noted above. I haven't received any complaints on being able to only copy 100 items in Quick Edit view at a time, but I have also noticed that issue. In my case, the retry doesn't work and I have to delete anything over 100 items before it will save. I would like to find a resolution on this as well. Every bit of help I can get with this issue is very much appreciated. Thanks in advance!