You may want to stop the On-access scanner when you perform system maintenance tasks. When you stop the On-access scanner, it will not start again in the current session or after reboot unless you do it manually.

You can stop/start the On-access scanner from a separate entry in the tray icon menu, or from the Configuration editor. Open the Configuration editor, go to the Components module in the Norman Virus Control configuration tree and unselect On-access scanner from the tabbed dialog Start.