Localizable string in Foundation.framework not found

If you don't specify "Document" then it will look in the file Localizable.strings. Otherwise make sure you have the file Document.strings in your project. Also, "(A Document Being Saved By %@)" looks pretty weird to me. You might want to check this is really what you want as a key for a localizable string.

Here is a link that may help you understand the process

https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/LoadingResources/Strings/Strings.html

I'm getting the same message. In my case it looks like both TestFlight and Crashlytics are generating them;

[TestFlight takeOff:@"xxxxxxxxxxx"]; // Generates 2 messages 
[Crashlytics startWithAPIKey:@"xxxxxxxxxxx"]; // Generates 1 message

Not causing us any trouble, so leaving them alone for now.

Update

Ok, got to the bottom of it. If you've been doing localization, chances are you probably enabled 'Localization Debugging' in your scheme (Product > Scheme > Edit Scheme in Xcode). If you're wondering why you're getting these messages from the various libraries, it's probably because you still have it enabled.

I just had this problem too.

Since turning off the warning seems like a bad idea (Feels like high risk translations will not work as intended), I tracked down what actually caused the problem.

In my case, the problem was an empty string in the Localizable.strings file. (I used a non-standard way to generate it, the default genstrings tool will not add them)

That is, in one place I had this line:

/* No comment provided by engineer. */
"" = "";

If I removed it, the warning disappeared! Seems like there is some problem in the string table implementation if you add empty strings, that makes all string tables mess up, not only the one where the problem is...

Maybe someone will find this information useful, so I leave it here.