# Anti-Virus Software on Windows If you want to disable Windows Defender you can use [Winhance](https://github.com/memstechtips/Winhance). **Any anti-virus software is only as good as its virus definitions.** If heuristics were any good they would've prevented outbreaks such as the last year's WannaCry outbreak which brought the British NHS to its knees. It could be argued that having an AV can decrease security as it **gives users a false sense of security, emboldening them to make riskier choices online.** Even with AV software you still have to exercise caution online. ## Avoid Non-Microsoft Products ### Due to Increased Target Surface Stay away form non-Microsoft products for several reasons. One is security itself. **Not only does anti-virus software provide hackers with a whole new attack surface, but it is also so close to the kernel that it’s a very tempting target.** Norton is infamous in this regard [^1]. Hacker groups started actively exploiting it in the early 2000s (back then it was the most popular AV). And it’s not a small attack surface either. I used to work a lot with hardware that uses COM ports; imagine my surprise when I found out that the driver vendor of the COM-to-USB adapters I used is 'Kaspersky Lab' (not my idea to use Kaspersky, IT mandate). **Security is all about trust, and any anti-virus software is so close to the kernel that it demands a lot of it. ==You simply have to trust Microsoft because they make the OS – but trusting Norton== with that much access ==is something else==.** [^1]: http://fortune.com/2016/06/29/symantec-norton-vulnerability/ ### For Compatibility **Non-Microsoft teams also have to play catch-up every month when Microsoft issues a new Windows Update, and if ==compatibility problems== occur that ==close to the kernel== it can easily ==lead to disaster==** [^2]. Avoiding any potential Windows Update issues should be a reason in and of itself. See [[Windows Update Horrors (in Serbian)]]. [^2]: https://support.microsoft.com/en-gb/help/4072699/windows-security-updates-and-antivirus-software Sometimes it‘s blue screens but sometimes the problems are much more silent and you find yourself banging your head for hours trying to figure out what is going on. That happened to me just a couple of weeks ago. I spent a whole day at the office trying to track down a bug that manifested itself with access violation, and sometimes even file not found exceptions, for a file our software created just moments before. To make matters worse it was only sometimes reproducible making me think it was a race condition. I was getting nowhere. And then a colleague suggested I turn Avira off (I switched jobs). Bug fixed. I couldn't find a solution in the end – only a workaround (for when Avira is running) that slows down a time-critical part of the app. And that’s not the only example I have from work – just this Monday a customer reported a bug he was sure was due to AVG.