VLC was slow on my Windows 11 PC until I found something to slow it down

VLC is probably the only media player I use regularly since Windows Media Player stopped being a one-time video feed on my computer. Most of you reading this are probably in the same boat. VLC even has advanced tricks that most users will never have access to. There’s a reason why it’s still the most popular media player on Windows and on PCs in general.

So you can understand my frustration when VLC started behaving properly about a month ago. Every time I started a video, the media player took an unusually long time to open. After researching the problem online, I discovered that Microsoft Defender was to blame thanks to a buggy Windows update that came out in August.

VLC has been getting on my nerves for the past few weeks

Even reinstalling didn’t fix the slow startup time

I use VLC regularly. Whether watching smartphone videos or local media on my computer, VLC has been integrated into my lifestyle for decades. So when it started starting up unusually slowly a few weeks ago, sometimes taking as little as 15 seconds, I was naturally annoyed. I didn’t change anything, so my anger was naturally directed at VideoLan.

At first I thought the new version was to blame, but there were no updates in August when this problem started. I’ve reinstalled VLC, no matter what the background adventure crashes, but the problem hasn’t really gone away. Additionally, my Windows 11 PC was experiencing other issues with File Explorer, so I attributed the slow VLC startup time to a problem with my Windows installation. It wasn’t until I googled the problem that I found the real culprit.

Microsoft Defender slows down VLC

Who thought?

The Internet was quick to condemn VideoLan, with some users even accusing Microsoft of deliberately slowing down the media player. On August 12however, the VideoLan team itself pointed out a bug in one of Microsoft Defender’s updates that caused the security suite to quarantine the VLC plugin cache. I only found out about this after the article took me to VideoLan’s X post.

Indeed, the latest Microsoft Defender update and Windows update KB5121003 have been shown to be responsible for this mess. Considering how many Windows updates have been flawed this year, I’d have to blame Microsoft. The plugins.dat file ending up in Windows Quarantine has slowed down VLC launch times worldwide, which is certainly one of the most surprising Windows failures.

Microsoft hasn’t fixed it yet, but you can do it yourself

Surprised, surprised!

At the time of writing, Microsoft has not released a patch to address the Defender bug that is causing harm to VLC. By the way, there are a few things you can do yourself to restore VLC’s launch speed. For starters, you need to reset the VLC cache affected by Microsoft Defender. You can reinstall or restart the media player to restore everything along with the cache VLC media player – reset preferences and cache files By typing “vlc” in the Windows search box.

Note that this does not prevent Microsoft Defender from quarantining the VLC cache again. So, you need to add an exception to the VLC directory Virus and threat protection settings. use Features section you can just specify the installed VideoLAN or VLC Select a folder on your computer to stop Defender from scanning it. While this isn’t a perfect solution, it’s the best we have right now.

Windows updates have gotten a terrible reputation lately

Microsoft seems to make more mistakes than it fixes with Windows updates. Sometimes it’s unexpected BSODs or deleted user files, and sometimes it’s boot loops or broken VPN configurations. This time, it’s a fake quarantine of the VLC plugin cache that has caused slow startup times for millions of users. Fortunately, despite the lack of official patches from Microsoft, users can easily fix the problem themselves.