MOMC error with XCode4 and Data Model Compile

Whenever I build my project, I'm getting the error:

Command /Developer/开发者_JAVA技巧usr/bin/momc failed with exit code 1

I've read posts here about deleting extraneous Data Model versions as a fix, and nothing works. I'm stumped because nothing changes the behavior of my Build: It always fail with the above error code, regardless of whether I actually have CoreData model files or not.

What I did to cause this error: Switched to a versioning model

What I tried:

• Removing new version of Data model
• Removing any old versions of Data model
• Removing entire versioning model and using previous version from Git
• Completely deleting any files or references to .xcdatamodel files (no coredata at all)

I've built clean between each attempt, and restarted XCode multiple times. Always the "exit code 1" error with momc.

Open up the .pbxproj file and manually remove all references to .xcdatamodel. Re-open XCode, Build Clean....and then drop in your older version of .xcdatamodel

For me the issue wasn't within the .pbxproj file.

Find the xcdatamodel file in finder. Option click and open package contents. Check to see if there are multiple versions inside that you don't recognise.

I was expecting only one version. A second version some how came about and xcode wasn't registering it.

I removed the second version and it's working fine now.