Xcode build & run error: “Process launch failed: Failed to get the task for process 216”

Question

After updating to Mavericks and making sure I got the latest updates of Xcode installed as well, Xcode suddenly fails to launch apps on the device.

It installs the app o

Answer 1

Figured it out. My Developer Certificate was marked as "Expired" in Keychain (search Spotlight for "Keychain", then click on the "user" tab on the left). I deleted it, then went to Xcode > Preferences > Accounts, selected my ID and clicked on "View Details", then clicked the Update icon at the bottom left. Xcode re-installed the renewed certificate. Then I went to Build Settings and manually set the Debug configuration to use the Developer certificate Xcode just reinstalled for me.