Error : failed to launch, when running on ipad

After much frustration I've finally got an application to run on an iPad without errors. However it doesn't run. It gives the following error. My application does run on the simulator but doesn't run on an iPad and gives the below error. I'm really not sure why. I went to the described folder the structure of the folder is as follows.

Products
 .DS_Store
  Debug-iphoneos
   .DS_Store
    sampleproject.app
    sampleproject.app.dSYM
  Debug-iphonesimulator
   .DS_Store
    sampleproject.app
    sampleproject.app.dSYM



error: failed to launch     '/Users/x/Library/Developer/Xcode/DerivedData/sampleproject/Build/Products/Debug-iphoneos/sampleproject.app/myProject' -- No such file or directory (/Users/x/Library/Developer/Xcode/DerivedData/sampleproject/Build/Products/Debug-iphoneos/sampleproject.app/myProject)

Solution

Just had the same error on Xcode 4.3.2, with target iPad3 5.1, but was able to build and run on my device after these steps:

  Deleted my DerivedData directory (emptied trash too)
  Quit XCode
  Disconnected iPad USB
  Rebooted Mac
  Rebooted iPad (power down and back up)
  Reconnected iPad USB.
  Restarted Xcode with project
  Confirmed build for debug on device selected.
  Clicked Run

I've no idea whether all these steps are mandatory. This is a crummy answer, since it neither explains the problem, nor offers a sure fix. I expect better of Apple; I've looked for a better answer, but found nothing.

Rebooting to solve problems is no solution! OTOH, it let me proceed on with my work, so...a small blessing.