(screenshots attached below)
Here I will be using My Sony Xperia SP to restore stock android system.
You need few things to do so.
1) Software : Sony Update Services. ( download this from Sony's Official Website )
2) Hardware : USB Cable and Sony Xperia Device
3) Active Internet Connection.
How to Do... Stepwise Directions.
STEP 1 : Download and install "Sony Update Services"
STEP 2 : Switch Off your Xperia Device and connect USB cable to Computer but not to Xperia.
STEP 3 : Open Update Services and click NEXT after accepting the agreement. Then select your device and proceed.
SETP 4 : It will take some time to download the software depending upon your internet speed.
STEP 5 : Now after downloading Update Services will install the software on your device... After Installing remove your Xperia and then switch it ON. It will take some time during first boot.
Congratulations, now you have the Stock Android Software on your Sony Xperia Device!!!!!.