We were making make iOS applications for our clients. After a round of testing within one of their departments, they found an issue and reported it back to us. We sorted out a fixed build for them.
Me: So here's the new IPA file.
Client: Ok, will do.
A few minutes later:
Client: It won't open.
Me: What do you mean it won't open?
Client: I tried to open the app and it just doesn't open.
At this point, I'm panicking. What's wrong with the app?
Me: I've checked over everything, installed it on multiple devices here, done upgrades from one version to another and it seems fine. What are you doing exactly?
Client: Just trying to open it, keeps showing an error.
Me: Ah! ok, can you screenshot and send me the error? *why he never told me that first god knows*
So he does. He sends me a screenshot of his desktop, showing a picture of Microsoft Word saying "Unrecognised file format .IPA"