Windows Defender Antivirus real-time scanning layer causing file modification blocks inside development source code repositories

Hi Oliver Mitchell

What’s happening here is that the real‑time scanning engine is watching every file operation inside those Git repos, and compilation loops generate thousands of reads/writes, so the overhead adds up fast. The way to fix this is by setting up exclusion paths in your endpoint protection profile. You’ll want to exclude the specific repo directories (for example C:\Users\<user>\Source\Repos\...) or even broader dev folders if that makes sense. Just be careful not to exclude too much you don’t want to open up the whole drive.

Another trick is to exclude by process as well (like msbuild.exe, dotnet.exe, or your compiler binaries), so the scanner ignores activity from those trusted tools. That way you keep protection in place but stop hammering the dev workflow. After you add the exclusions, push the updated policy to the affected endpoints and have the teams rerun their loops. You should see compile times drop back to normal. If this answer helps you move forward, please hit “accept answer” so we know we’re heading in the right direction and let me know if you need any assistance. Thank you!