Windows Security Center won't update

Registration date
Tuesday March 31, 2015
Last seen
October 9, 2016
- Oct 9, 2016 at 11:49 PM
Hello, My Dell Inspiron 1525 running on Vista can't seem to install any more updates on the Security Center. I hadn't realised that it's been a LONG time since the last time it announced me there were updates to be installed. I have it set on automatic, but it just doesn't do it. Every day Defender also tells me it's out of date. When I try to do it manually, it does nothing.
Now I went through Panel Control and clicked Update Now, and it's not going anywhere. This has been it for the last 30 minutes.

No new software or hardware, I have Avast running but it's always been that way, even when it worked fine. Connection is fine also.
Nothing. Is there any way you can help me solve this?