Part of the process of setting up iOS apps for push notifications involves signing and submitting certificate signing requests in Apple’s iOS Provisioning Portal. Typically, if you can read and follow directions, this is not too big of a deal. However, if you do end up getting the dreaded “The Certificate file is invalid. Please check the file and try again.” error, then the cause may just have nothing to do with you, and everything to do with your browser.
I have run into this a couple of times now, and both times it was because I was using Google’s Chrome browser. For whatever reason, Chrome can’t seem to play nicely with the iOS provisioning portal and screws up the upload. If you switch over to Safari, you should have no problems submitting the certificate signing request. If you are still getting an error, then the problem is some where else.
If you get this screen and are using Chrome:
Switch to Safari and you should get this:
Moral of the story: