We are building an app that is deployed on a range of Customer iPads via AdHoc. Testflight works great with that, however our latest release refuses to install on iPads that have the latest version of iOS (5.1) installed - we previously deployed successfully to these iPads and their UDIDs are definitely in the mobile provisioning profile. Also the same build installs fine on an iPad that has an older version of iOS.
I already suggested to re-register the device as per the TestFlight FAQ article, but that didn't help. It seems to be a problem with iOS 5.1 - the user is asked to 'Contact the Developer' as the device does not have permissions.
Has something changed with iOS 5.1 re: the requirements for AdHoc deployment? We are building using the distribution profile, signing with the distribution certificate - and as I said, the app installs fine on iPads runnin older versions of iOS.
After installing iOS 5.1 I suddenly had similar problems with some of our testers.
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