Consider installing the anti-malware program, Hitman Pro
Hitman Pro can detect malware without relying on specific digital signatures of problem files that a vendor has determined are malicious. It will identify malware files solely based on how they operate. Hitman Pro will not take up a lot of system resources because it does not download virus definitions but instead analyzes them remotely. The downloaded files for Hitman Pro should only take up 12 MB of space on the hard drive.
You may have heard that it's not advisable to run more than one anti-virus program on your computer, because if they operate simultaneously they will degrade your PC's performance. Hitman Pro is designed to run simultaneously with other security software. Hitman Pro can help detect rootkit malware that is designed to circumvent security software. If HItman Pro detects a suspicious file, it will check it against lists of malware maintained by 5 other vendors.
Hitman Pro can disguise itself as a virus researcher (such as a sandbox -which can detect malware without prior knowledge of its existence) so that sandbox-aware malware will shut down.
Download the trial version of Hitman Pro here.