Unity IOS: Able to compile for running, but XCODE gets stucked if I try to Archive

Hello all,
I have been trying to compile a game made with unity IOS and it worked fine if I want to run it in my Iphone, but when I try to compile it for “Archive”, XCODE gets stucked here:

I have a correct provisioning profile, and also the certificate, and if I compile from Unity using Monox2 it works here perfectly. I was able to create the app and also able to make the validation process, but apple needs 64 bits now so I had to compile from Unity again.
I am using Unity 4.7 and Xcode 7.1.

Any Idea? I have been 3 days trying to solve this and I don’t know how to proceed.

I have found a possible solution here:

http://stackoverflow.com/questions/12944175/xcode-4-5-1-get-stuck-when-archiving/12988404#12988404