Category: Viruses and Spyware
Type: Win32 worm
Prevalence: Small Number of Reports

Download Download our free Virus Removal Tool - Find and remove threats your antivirus missed


  • Backdoor.Rbot.gen


  • Allows others to access the computer
  • Steals information
  • Records keystrokes
  • Installs itself in the registry
  • Exploits known vulnerabilites

How it spreads

  • Downloads

Affected Operating Systems


Recovery Instructions:

Please follow the instructions for removing worms.

You will also need to edit the following registry entries, if present. Please read the warning about editing the registry.

At the taskbar, click Start|Run. Type 'Regedit' and press Return. The registry editor opens.

Before you edit the registry, you should make a backup. On the 'Registry' menu, click 'Export Registry File'. In the 'Export range' panel, click 'All', then save your registry as Backup.

Locate the HKEY_LOCAL_MACHINE entries:

Microszoft Update Machinezs = mscnsz.exe

Microszoft Update Machinezs = mscnsz.exe

and delete them if they exist.

Each user has a registry area named HKEY_USERS\[code number indicating user]\. For each user locate the entry:

HKCU\[code number]\Software\Microsoft\Windows\CurrentVersion\Run\
Microszoft Update Machinezs = mscnsz.exe

and delete it if it exists.

Close the registry editor.

  • Check your administrator passwords and review network security.
  • Download and install the Microsoft patches mentioned. On standalone computers, update with all relevant security patches from Windows update.

download Try Sophos products for free
Download now