I have done what QA1764 says and I still get an "iTunes Sync: Failed to install" dialog on my iPad after syncing through iTunes. No Xcode errors prior to that. I tried both of my "Development" certs, not the "Distribution" cert. Unpacking the .ipa and running "codesign --verify -vvv" says all is good.

Console log on the device says:

001f8000 verify_signer_identity: Could not copy validate signature: -402620394

If you can make this work and can tell me what you did, in explicit detail, it would be appreciated.

Fucking codesigning. What a crock of fermented shit.