BleepingComputer Review:

Farbar Recovery Scan Tool, or FRST, is a portable application designed to run on Windows XP, Windows Vista, Windows 7 and Windows 8 in normal or safe mode to diagnose malware issues. It is also possible to run FRST in the Windows Recovery Environment in order to diagnose and fix boot issues.

This program will display detailed information about the Windows Registry loading points, services, driver services, Netsvcs entries, known DLLs, drives, and partition specifications. It will also list some important system files that could be patched by malware.

Note: There are both 32-bit and 64-bit versions of Farbar Recovery Scan Tool available. Please pick the version that matches your operating system's bit type. If you don't know which version matches your system, you may try both of them. Only one of them will run on your system.