Ipad w/9.3.1 wont download apps - Says file is Corrupt

I have an older ipad that I updated to the new 9.3.1. But none of the apps from the app store will download. Either says that file is corrupt, or just keeps cycling and does not download. Also keeps saying it cant log me into the APP store on the ipad. No problem with that on itunes. Tried to reset the whole ipad and that did not help. Tried to install apps via itunes and that did not help. Keeps saying the file is corrupt.

Backed up and completly restarted the system 2 times. No change.