I am using Windows Vista. It is working fine and there is no issue with that. But there is some issue with the system recently. I cannot run Task Manager. When I right click on the Task Bar it shows a grayed out button. After a few while the Task Bar stopped working. There is no response on it. It looks like it is complicated locked. I cannot click on Start Menu. The desktop works fine. I can open My Computer and check internal files.
Bookmarks