How do I clean Virtual Memory?/increase?

(On windows XP/Win server)

1. right click on My computer and go to properties
2. go to advanced Tab
3. In performance groupbox click on settings button
4. go to advanced tab
5. In Virtual Memory groub box click on change button


Now u can change virtual memory from here. Plz note if u donot press the set button after making changes then the changes are lost.