How do I extend the virus scan past my C drive so that it scans my D and M drives?
If by "extend the virus scan" you mean "perfom scan for other drives" -- most likely there next meanings:
--> So called "Virus scan" is a brief-check about places/destinations - where most likely can be troubles; Like active malware or so;
--> For detect "not active" malware (or kind of this) under system; Or as scanning for full drives:
-- DESIGNED steps: there possible to launch "Full Scan";
^ under this help you have to use steps about "Full computer scan" (Main UI F-Secure SAFE -> 'Tools' tab -> Scanning options -> Full Scan);
-- OR you able to "choose" drives under Explorer (like target files) -> rightclick and choose context-manual scan;
-- ALSO there is "real-time scanning" - which scan all (?) drives at access or activities;
-- ALSO possible to configure scheduled scan;
-- MAYBE if you want certain "virus scan" (or certain options) - maybe you able to use commandline scanner as "task under system" with certain configuration; But this is not common steps;
Sorry for my reply.