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Windows Defender blocks Unreal Engine 5 installation

I cannot install Unreal Engine Early Access, because Windows Defender seems to block it, reporting a specific component of the installation:


The installers error code is IS-MF01-225-225.

Is it safe to install this 3rd party (see path in screenshot) tool coming with UE5?

This error should probably be fixed, because it will keep many from installing it on Win10, when Windows default antivirus, active by default, stops the installation process.

I would have reported it to an issue tracker, but I can’t seem to be able to find a way to submit an appropriate ticket somewhere?

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Got the same issue today!
MS Defender declares it as Trojan:Win32/Zpevdo.B threat description - Microsoft Security Intelligence

Download and installation went trough without any issues today. Interesting, the file that has been marked is not included any more. (disabled iOS and Android packakes for the dowload)

Just chiming in to say I’m having the same problem.

This is false positive, report that to microsoft.
Or disable microsoft defender for insttallation.

There were some false positives in past (for epic installer).

Last time it was because epic made some “custom installer files” that honestly looked like malware (they had no malicious code, just structure similar to known malicious applications).

So those files are sometimes falsely detected by various AV programs.

For those more paranoid:

  • make/calculate sha256 of detected file
  • submit that sha256 to virustotal, see detections.
  • if file is not there , just upload it for scanning.

Those false positives are usually removed after few days.

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