xcode 4.2, code signing for distribution

The method you described deviates a little from the method that I just recently used. Try following this guide:

http://www.touch-code-magazine.com/how-to-upload-an-app-to-the-app-store-with-xcode-4/

It worked perfectly for me and seems to be a different method than what you did. It uses the xcode interface directly to go all the way through the upload process. (aka, you don't need to manually upload the file via your internet browser)

EDIT:

Also try: http://www.weston-fl.com/blog/?p=2442

I had the same issue when I archived the app, I got the message "codesign wants to sign using key <key> in your keychain." <key> should have been 'my distribution certificate name', went to all the steps what could be wrong:

• distribution certificate was correct in keychain
• deleted all old certificates
• checked if the mobileprovision was valid in terminal

but that didn't work. Finally contacted apple support and pointed me to https://developer.apple.com/legacy/library/technotes/tn2250/_index.html--> Configuration Troubleshooting

Followed these steps (see for more details the link):

• deleted all distribution certificates in keychain
• also deleted provisioning profiles
• revoked the certificate on the developer account site
• created new certificate
• renewed distribution provision files (on the site)
• downloaded and dragged/dropped the new certificate and provision file in xcode

Note: In the troubleshoot session it says you can renew using Xcode, I did not work for me as I got the message that "There is already a certificate request pending", manually did the trick...

I had ever ran into similar issue which is because I installed xcode 4.0 after 4.2, it is solved by re-install xcode 4.2. You may have a try.

For technical support, you may request tsi (http://developer.apple.com/membercenter/index.action#techSupport)