Windows 8 -8.1?

[Exploration]

Wow the above is actually incredibly helpful. Might as well dig up the defender error code/message while i'm at it and make another feature work. Though Malwarebyes is going on regardless, i've used it on my laptop before and found it a magical little program (Many thanks for the link by the way, makes things a bit faster )

Windows Defender:
Whenever i open it through control panel and hit the 'Turn on' button as it keeps sending me alerts my antivirus is turned off. But each time i do so it appears with an error message: "Windows Defender couldn't turn on real-time protection.
This operation returned because the timeout period expired.
Click help....Blah blah.

Error Code: 0x800705b4"

I have already googled said error code and all Microsft could suggest when i found a thread about it was i install the latest definitions. It's since then downloaded nearly 200MB of Defender updates and still no joy, kinda strange little glitch