install.log definition, relationships, removal:

This is a part of a malicious parasite that violates user privacy and damages the compromised system. The install.log file can be used for different purposes depending on the related parasite's type, functionality and carried payload. Although install.log may not take any malicious actions by itself, it ensures that a parasite is working properly and therefore needs to be removed. DO NOT open, execute or edit install.log!
The install.log file is installed and used by keylogger Codename Alvin. It is also related to other parasites such as keylogger Cyber Predator, keylogger Desktop Spy, keylogger Invisible Keylogger 97, keylogger PC Weasel, keylogger Perfect Keylogger, keylogger RoboNanny, keylogger SC-Keylog, Telephone Spy, InternetAlert, VCatch, MarsPC, LinkGrabber 99, NetSonic and Dope Wars. These threats can use install.log for different purposes, as the file's functionality depends on a particular parasite it belongs to.
Please note that the install.log file actually may be a fully legitimate part of the operating system or legitimate software. Often parasites use files with unsuspicious names, but malicious functionality. You should always carefully check the file before deleting it. It may not be related with malware, but can be required by your essential programs to work properly.