Having updated and run both SUPERAntiSpyware and MalwareBytes Anti-Malware (with clear results), Avast AntiVirus detected the following 'malware' - JS:Pdfka-NH [Exploit] within the location C:\FOUND.067\FILE0000.CHK
I was able to delete it but I've noticed that there are several of these C:\FOUND.0## folders, and am unable to find them even with a file search.
What are they for and, assuming I can locate them, should they be deleted?
A search engine suggests BrowserModifier:Win32/Fotomoto and TrojanDropper:Win32/conhook. Right click Avast in notification area and click start Avast antivirus. To speed things up then click on 'stop memory test'. Right click the console or 'skin' and select ' schedule boot-time scan. Select all local disks. Click on the schedule tab. Select 'yes' at the new prompt window. Your PC will reboot. You will need to attend the scanning (prior to Windows booting) to determine to delete or quarantine any viruses or trojans.
Not had any problems before finding the above malware - bit remain suspicious of any folder(s) that remain invisible (as these do) even when folder view options are set to show ALL, including system/hidden folders/files.
No rootkits then. Suggest running Ccleaner (in default settings) and also run the registry cleaner. Make a backup when prompted. Found in 'my documents' as default. Note 'history' and passwords will be lost.