A friend of mine says she has 'lost everything' on her PC because of a (she says McAfee type) virus. I was just wondering whether this is likely or whether it has just hidden her files?
It has likely just hidden her files. If it's a virus and not just scareware, then it's possible it has overwritten her master boot records and her registry. More likely, though, it's scareware and it's simply hiding her files.
The best thing she can do is to download this:
rkill:
Download Link for rKill
and this:
MalwareBytes:
Download Link for AMB
Have her restart her computer into safe mode (when the screen goes black before the Windows logo, have her press the F8 key and choose Safe Mode), and run the rkill program.
Then have her install and run Anti-Malware Bytes. Let it scan everything and remove whatever is causing the problem. Upon startup into regular Windows, click on the START menu and have her choose "Run".
Have her type "cmd" (no quotes).
In the black command prompt box, have her type the following:
attrib -s -h /s /d *.*
It will unhide everything hidden by the scareware program.
That should resolve the issue if it's just scareware.
If it's actually a virus, she'll have to use a good antivirus program (I recommend Microsoft Security Essentials, it's free and great! Get it
HERE), clean the system and simply load a system restore point before the virus was on the system.
I hope that helps her!