Can't turn 'System Protection" on

My system protection is displayed as "off" but the button to turn it on is grayed out. When I click System Restore I get the window with the "configure system protection" hyperlink but clicking it has no effect, nothing happens. Why would it be disabled? I have created RP's before. Why is it turned off & how do I turn it on.
RE sysinfo below;I don't understand the last sentence about WinDef antivirus being off. ContPanel says WD is on
Here is a screenshot of the windows:

http://imageshack.com/a/img633/4197/7NFYli.jpg

TSG: SYSINFO:
Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1, 64 bit
Processor: AMD A10-6700 APU with Radeon(tm) HD Graphics, AMD64 Family 21 Model 19 Stepping 1
Processor Count: 4
RAM: 11461 Mb
Graphics Card: AMD Radeon HD 8670D, 768 Mb
Hard Drives: C: Total - 932868 MB, Free - 586652 MB; D: Total - 19137 MB, Free - 2343 MB; E: Total - 1907726 MB, Free - 561508 MB; F: Total - 953867 MB, Free - 597397 MB;
Motherboard: MSI, 2AE0
Antivirus: Windows Defender, Disabled