Backdoor.Graybird.C is a Backdoor Trojan and a variant of Backdoor.Graybird.
It gives a hacker unauthorized access to your computer. It opens port 52013 to listen for commands. The existence of the file, HGZSERVER.EXE, is an indication of a possible infection. The Trojan uses special icon to attempt to disguise itself as an ordinary .txt file.
Starts an FTP server on port 21, which allows the hacker to use the compromised computer as a temporary storage device.
To disable activity of this worm navigate to each of these the keys:
and delete the value - huigezi %System%\HgzServer.exe
Also, make the changes in the Win.ini file
Use antivirus (also check How To Remove section)Startup Optimizer to remove it from startup.