I cannot seem to be able to archive an app on a new computer. I created new provisioning profiles for distribution and development. I created a new Certificate Signing Req
Given up on all of the above. The only thing that worked for me was:
On step 7, xcode requested access to keychain (which it did not do in other solutions stated above), once granted - it worked.
Same for step 8.
Not sure what was going on (my certs and profiles were only 3 months old), and I admit this was a 'brute force' method - but it worked.
Good luck.