Build and go on Device under Debug error

Question

When I try to build and go an application I made on my device (iPod Touch) I get the error
Command usr/bin/codesign failed with exit code 1
Help would be appreciated,
Mr. Man

Answer 1

Ok, here are some more easy questions for you before this starts getting hard:
1) Have you ever successfully run one of your Xcode projects on your device? If so, was that prior to installing either iPhone OS 3.1.2 or Snow Leopard?
2) Please confirm the version nos. of your OS X system, your iPhone SDK and Xcode.
3) Open the Keychain Access Utility (navigate to /Applications/Utilities with Finder), select login from the top left Keychains panel, and _My Certificates_ from the lower left Category panel. You should now see iPhone Developer: <your company name> in the right-center list, and when you expand that entry, you should see your private key. Double click on each of those in turn, and look for any irregularities, such as expiration, wrong name, etc. When your certificate is selected, the info above the list should display a checkmark in a green circle to the left of the words "This certificate is valid".
4) Return to Project Info (Project->Edit Project Settings), and take another look at Code Signing Identity. The left hand setting should probably say "Any iPhone OS Device". The right hand should probably say "iPhone Developer (currently matches <certificate> in <profile name>), where <certificate> is identical to the uppermost line above the green check mark in step 3, and <profile name> is the name of the provisioning profile shown in the Xcode Organizer window when your device is selected in the left panel (and in that left panel, the device selection should show a small green icon on the right side of the panel).
Please be sure to let us know about any deviation from what I described in steps 3 and 4.
If you still have no clues, please return to the Portal, and start from the beginning of the instructions for getting ready to test your projects on a device. Pay special attention to the How To tabs for Certificates, Devices, App IDs, and Provisioning. Also note there's a User Guide, and 4 videos available under Portal Resources in the upper right panel of the Portal home page.
If you don't see what you missed after studying the above, start a new project from a clean template. The name for the new project should not contain any spaces, and the logs will be much easier to read if you save the project folder close to the root of your file system. Then repeat every instruction in the Portal for that project and try to install it on your device without making any other changes to it.
If none of the above is helpful, search this forum on keywords such as codesign, signing, identity, 3.1.2, 10.6, snow and SL, along with some of the terms you found in the build log, such as "invalid existing signature". As you'll see, if this forum had a FAQ, codesign problems would be at the top of the list. If you don't get a clue from searching this forum, put the same keys into Google.
The above is an overview of what questions need to be answered and where to look, starting with the easiest and progressing to the more difficult investigations. If you think you've found a clue, but don't know what to do with it, please let us know right away.
\- Ray