Hello. I have a few PC's here both vista and windows xp, and they have windows defender installed. Well they have all started asking to check for updates for windows defender. When i click on the button to do the upades it scans and says there are no new updates. Afterwards it keeps showing the icon in the taskbar asking to check for updates. And in windows vista it also has a security icon showing saying defender is out of date. How do i solve this issue? Why wont it realize that there are no new updates? Where can i manually download any new updates and install them? Thanks in advance for any help anyone can provide.