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Windows Defender Engine Unavailable: How to Fix This Error
Run the Windows update troubleshooter or tweak the registry
5 min. read
Updated onMarch 29, 2024
updated onMarch 29, 2024
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Key notes
You will findmultiple user reportson users complaining about an error that readsWindows Defender Engine unavailable. This prevents the users frominstalling the security updatesand also does not allow them to safeguard their PCs against threats.
Suppose you are also facing similar issues and are looking for solutions. In that case, we suggest you check out the solutions mentioned in this guide and hopefully fix the Windows Defender engine unavailable error. So let us get right into this guide.
Why am I getting the Windows Defender engine unavailable error?
Take a look at the most common reasons that could trigger theWindows Defender Engine unavailableerror we found out after carefully digging through the internet:
How can I fix the Windows Defender engine unavailable error?
1. Run the Windows Update troubleshooter
Some typical issues can be easily fixed by running the Windows Update troubleshooter. For example, you can follow the above steps and check if this resolves the issue of Windows Defender Engine beingunavailablebecause the definition updates for Windows Defender are rolled out via Windows updates.
2. Manually install Security Intelligence updates
If the Windows update isn’t downloading for some reason, you can manually download the latest security update on your PC.
3. Fix corrupt system files
You can take the help of the in-built SFC Scan, and DISM commands to fix corrupt system files or missing system files and also resolve several problems. However, these SFC and DISM commands often don’t help improve the corrupt system files.
So, we suggest you use a dedicatedsystem repair and optimization software. With these tools, you can fix system crashes, and damaged DLLs, remove ransomware from your PC, and much more.
4. Tweak the Registry
5. Reset Windows Security
There might be some issues with the program which is why it can’t load all the files correctly. In such a case, you should reset the Windows Security tool and check if this resolves theWindows Defender Engine unavailableerror.
6. Reset your PC
If none of the above solutions fixed the problem for you, you should go ahead and reset your PC following the above steps, as this would help you reset your PC without deleting your files.
That is it from us in this guide. We have a guide that will help users facingthe Virus & threat protection option that isn’t workingon their Windows 11 PC.
You can also refer to our guide on the missingWindows Defenderfrom your Windows 11 PC, which will help you resolve the issues and get back to Windows Defender pretty quickly.
Feel free to share your views on which solutions helped you fix the Windows Defender Engine unavailable problem in the comments below.
More about the topics:Windows Defender issues
Sagar Naresh
Sagar is a web developer and technology journalist. Currently associated with WindowsReport and SamMobile. When not writing, he is either at the gym sweating it out or playing country music on his guitar.
He is an avid traveler and has been to 15 countries, going to more places soon. TRAVEL and WORK is his mantra for a peaceful life.
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