iPhone 5s reboot issue with iOS 8.3

I never faced reboot issue in iphone till i upgraded to iOS 8.3. After upgrade I faced random reboot with blue screen issue.

Sometimes it was rebooting in loop & recovering after few reboots.

But, from last two days, it is rebooting with blue screen after showing apple logo & not recovering.

After going through community discussion, I tried to restore/reset in recovery mode. After extracting the software I get error 14!! 😟

Tried to downgrade to 8.1 version. Getting error 3194.

Even tried clean/new installation of i-Tunes & then restore. No luck with that 😟

Error is taking to Resolve iOS update and restore errors in iTunes - Apple Support.

I am on latest iTunes(12.1.2.27 64 bit), Windows System(64 bit), Antivirus switched off, No extra USB cable connected, Windows update is done as suggested, restarted system & device.

Can someone please help to recover the phone?