Show installed updates in Windows Vista
Windows Vista keeps a log of every Windows Updates ever installed on your computer; any time an update is successfully applied to your system, Vista will add it to the archived list of updates. This list can be used to roll back or uninstall Windows Updates, if needed, without using system restore. This tutorial explains how you can access the list of old updates installed on your PC.
Open Windows Updates in the Control Panel
To access the Windows Updates applet, go to the Start Menu, and click Control Panel; then, click on System and Maintenance. Finally, click on the "Windows Updates" header-link.
If you are using Windows Vista's Classic Start menu, go to Start > Settings > Control Panel > Windows Updates.
View Update History
Once the Windows Updates screen has loaded, locate the View update history link in the left side pane and click on it.
Windows Vista will open the View update history screen, and include a sort-able list of all updates ever installed in Vista (these would not include updates installed under Windows XP if you upgraded your computer from XP to Vista) - Windows updates, Microsoft updates for other Microsoft products, and driver updates you installed in the past:
To view the description of a given update, right-click on it and choose View details; the "Copy details" command on the same context menu simply copies the entire information available about the update to Windows' clipboard. Note that this list is "read-only", and does not let you delete or uninstall Windows Updates, which we explain in the other linked tutorial.
Each column header is clickable: click once to sort in ascending order, based on the values contained in the column; click again, and Windows Vista will display the same contained values in descending order.