28,660 questions
Update and Reset 3D Builder.
Ensure that 3D Builder is allowed through your firewall.
If the issue persists, then try using online STL repair services.
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My internet connection is excellent, so the issue can't be on my end.
Update and Reset 3D Builder.
Ensure that 3D Builder is allowed through your firewall.
If the issue persists, then try using online STL repair services.
I had the same problem, but I found this website https://windows.apkpure.com/3d-builder/versions that allows you to download different versions. Once you install one of the newer versions, it will update your 3D builder app, and you'll be able to repair.