iOS 9.1 ipad cannot connect to the App Store
I went to a Genius Bar to fix this.

The genius said that I needed to reinstall 9.1. He said that sometimes when 9.1 is installed something gets messed up, so it needs to be installed TWICE.

Unfortunately, you can only do this from a PC or Mac desktop computer, because iOS on the iPad does not give any option to re-install an operating system you already have.

After re-installing 9.1 the App Store did indeed work on my iPad.

Note that this machine is an original iPad.



Also, another important note is that the App Store can get munged if it is accessed from a blocked network. If you trying to use the App Store from a place where there is a firewall or advanced packet filtering, like a company network, then the App Store can get blocked and this will mess it up because it will timeout and then not attempt to connect again. The App Store uses many different ports and if any of these are blocked by a firewall, it can get messed up.

To fix this:

(1) get a clean, unblocked, unfiltered connection

(2) close any open instance of the App Store by using a 4-finger swipe up

(3) start App Store again