Version of iOS on device does not match any of the versions of iOS supported for development 

I ran into this little problem the other day after updating my Ipad to 4.2 (or at least that is when i first noticed the problem) and it would keep me from installing my apps from Xcode into my device

The version of iOS on “The Evil One” does not match any of the versions od iOS supported for development with this installation of the iOS SDK. Please restore the device to a version of the OS lister bellow, or update to the latest version of te iOS SDK;…

And then it would show that the OS Installed on my Ipad matches exactly the Xcode supported version, thus, contradicting the message’s text.

Trying to make sense of this error did not give any results and Googling this problem did not help much. I went to the developer forums where people asked me if the device had been jail-broken or if i had used any betas of the SDK: to both the answer was no. After that pretty much everyone was stomped and i was told to go to the MacStore and check for a hardware error.

I restored my ipad and gave it a clean install (loosing all my data, i guess this is why you are supposed to have a spare Ipad/Iphone for development) but still the error persisted. I was about to go to the MacStorebut i decided to try something else before doing that, just in case.

For those having the same problem upgrading to 4.2 here’s what worked for me: Unistall and Reinstall Xcode. I did have the latest version but for some reason doing this made the problem go away.

After i followed the instructions on this post and re-downloaded and reinstalled XCode, my Ipad went back to functional status.

This is the first time i had to wipe my Ipad and i was very glad to see that the infamous Kindle app actually keeps an online Library of all my purchased books, so i didn’t loose them.

Now if only i had backed up my Epic Win progress…