You cannot manually run a scan that is scheduled. Scheduled scans are displayed in the Available scans list with a clock icon.
To run a manual scan on demand, you must first create an Available scan. To create an Available scan, see the Setting Up a Scan section. (You will only need to do this the first time you want to run a manual scan.) Once you have created an additional Available scan, it will appear in the Available scans list in the home page of the Sophos Anti-virus window.
To run a manual scan on demand,
Select the scan you want to run by highlighting with a single click.
Click "Scan local disks."
A progress dialogue box will be displayed and the Activity summary will appear in the Sophos Anti-virus window.