If you used R.A.T on iOS 8 and are lucky enough to have a device that still boots, follow the instructions below to get it running normally again. In most cases using R.A.T. (on iOS 8 ) will effectively "semi-remove" your jailbreak. Symptoms include apps instantly closing on launch, Cydia icon completey missing, Wifi grayed out and unusable, among others. To fix this:
Run Taig or PP jailbreak again (this is one of the few scenarios where you can actually "re-jailbreak" a device without doing a complete restore first).
At this point after successfully "re-jailbreaking", Cydia should reappear and be usable again.
Intall OpenSSH from Cydia.
Download SemiRestore from
www.semi-restore.com, connect your device via USB, and run the tool. See this tutorial for more info.
If after running SemiRestore you encounter network or activation issues, simply run SemiRestore a second time.
That's it! Your device should now be back to a normal, fully functional jailbroken state.
Here is one recent example of this being resolved by using the steps above.
Needless to say, anyone on iOS 8 should stay as far away from iLex R.A.T. as possible!!!