Whenever any of our staff attempt to install our app from testflight, we are getting the message "app cannot be installed because it is invalid. Please try again', and we have been unable to install the app as a result. I have tried a rebuilding etc to see if it was just something that went wrong with the build but the error still happens. Deploying to our local and virtualised devices works fine though.
Are there any steps to be able to get more detail or validate the ipa file to see why this message is occuring? We have previously deployed the same application with testflight some time ago and it worked fine, so i'm unsure why it has failed this time.
