Back-up brain because I know I’ll forget this kind of thing. Was trying to target some Xcode projects to a deployment target of 4.2 and to a device rather than the simulator. Wasn’t getting them running, or rather they would seem to run an finish almost immediately. In the console entries like

Fri Nov 18 23:51:16 unknown lockdownd[16] : 2ffea000 handle_connection: Could not receive USB message #6 from Xcode. Killing connection
Fri Nov 18 23:51:16 unknown com.apple.mobile.lockdown[16] : Could not receive size of message

Found the tip about adding armv6 helpful but it was only working for Apple sample code projects and not new projects created by myself. Eventually tracked down that there’s an entry in your Info.plist, Required device capabilities which is set to armv7. Eureka! changed that to armv6 now the apps run fine on the device. Grrr took most of the afternoon to find that though. It’s bringing back memories developing projects in C 20 years ago – just one wee bit of your make file out of sorts and all sorts of mayhem ensue. Aha nice to see we’ve moved on, now you get to stare and swear at a GUI instead of a command line. Same old, same old