About scanning for rootkits

You are strongly recommended to close down all non-essential applications and allow Windows Update to complete before scanning for rootkits.
Depending on the computer being scanned, a Sophos Anti-Rootkit scan may take anywhere between a few minutes and over an hour to complete. Scans generally take significantly longer to complete on a server computer. You can stop a scan at any time, but the results will be incomplete, so run a scan at a time when it will cause least inconvenience.
When Sophos Anti-Rootkit cleans up a rootkit from your computer, a restart is required to complete the process.