Um einen neuen Viruskiller installieren zu können muss man zuerst den alten deinstallieren. Dies kann aber oft zu Problemen führen wenn es keinen Uninstall gibt. Hier die wichtigesten Tools um dennoch den alten Viruskiller weg zu bekommen.

• AVAST! Removal Tool – avast! uninstall utility
• AVG Antivirus – AVG Antivirus Remover utility
• Avira antivirus – Uninstall Anleitung für Avira. Avira AntiVir Registry Cleaner Tool
• BitDefender Antivirus Removal Tool: BitDefender Uninstall Tool
• BullGuard Antivirus – BullGuard uninstallation Tool
• Computer Associates – Uninstall Anleitung
• Uninstaller for CA Internet Security Suite 2007 & 2008
• Uninstaller for CA Internet Security Suite 2009
• Comodo AntiVirus – Uninstall Anleitung
• Dr Web – Download Page. Removal Tool - Download.
• eScan MicroWorld - Removal Tool – Download.
• ESET NOD32 Antivirus Removal – Uninstall oder Reinstall von ESET Smart Security/ESET NOD32 Antivirus?

• ESET NOD32 Removal Tool (Französisch aber funktioniert für alle Sprachen)
• Etrust – UninstallWithGUI.exe
• F-Prot - Uninstall
• F-Secure products – Uninstall, F-Secure Uninstallation tool
• G DATA AV-Cleaner – G DATA AVCleaner
• Kaspersky Anti-virus Removal Tool – Uninstall, KAVRemover
• K7 Total Security - K7RT.exe
• McAfee Consumer Products Removal Tool  – Use on McAfee, AOL distributions of McAfee, CA distributions of McAfee – McAfee Consumer Products Removal tool (MCPR.exe)
• Microsoft OneCare Uninstall Cleanup Tool  (All versions; XP & Vista) – Windows Live Onecare Cleanup Tool.exe
• Norton/Symantec Removal Tool – Norton Removal Tool , Norton Entfernen
• Norman antimalware – Norman Virus Control / Norman Internet Control
• Panda Antivirus Uninstaller- Panda Uninstaller.exe, how to, Panda 2008, Panda 2009, Panda 2010, Novell, Admin Secure, Protectionmodul,
• PC Tools Antivirus – PC Tools Community Forum – Uninstall PCTools
• TrendMicro Products – Anleitung, Anleitung zur Deinstallation von Trend Micro Internet Security Pro und Trend Micro Internet Security – 32-bit | 64-bit
• VIPRE Antivirus + Antispyware – Sunbelt Software VClean.exe, AgentRemoval3.1.exe
• Webroot -  Anleitung
• OneCare - OneCareCleanUp.exe
• Windows Security Essentials - Anleitung

Weitere Uninstall Tools:

• OPSWAT AppRemover – What is AppRemover? AppRemover enables you to thoroughly uninstall security applications such as antivirus and antispyware from your computer.
• Windows Installer Cleanup Utility - Anleitung für Windows Installer CleanUp Utility
• Malwarebytes’ Anti-Malware Clean Utility
• SUPERAntiSpyware Uninstaller Assistant
• ThreatFire removal tool (für Version 3 und 4)
• ZoneAlarm Products