If you open task manager (right click the taskbar and select is one way) then scroll down under the process tab and find windows explorer, or it might be explorer.exe on your Vista, right click and select 'open file location'. Scroll down in the file that's opened, find explorer.exe, right click and select 'send to'. Select Desktop (shortcut). That should give you easy access to explorer. You could then pin to taskbar. I'm on windows 8 but shure the paths are similar in Vista.
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