When Git triggers this, it’s almost never because of a typo in your command. Instead, it’s typically an between Git’s build of libcurl and the SSL/TLS backend available on your system. Common causes on Windows 1. Broken or missing SSL/TLS backend Git for Windows can be built with different SSL backends: OpenSSL , Schannel (Windows native), or Secure Channel . If your Git version expects OpenSSL but can’t find its certificates or DLLs, libcurl rejects internal arguments. 2. Conflicting http.sslBackend setting Manually setting git config --global http.sslBackend to a backend that isn’t compiled into your Git build triggers this exact error. 3. Corrupted Git installation or mixed installations If you have multiple Git versions (e.g., GitHub Desktop’s bundled Git, Cygwin Git, and official Git for Windows), environment variables like PATH can cause libcurl to load mismatched dependencies. 4. Proxy or custom http. configurations Unusual proxy settings or malformed http.sslCert / http.sslKey paths can also pass bad arguments to libcurl. How to fix it Step 1: Check your Git + libcurl version git --version curl --version Look for the SSL backend line, e.g.:
Here’s a structured blog post draft tailored for developers encountering the curl: (43) A libcurl function was given a bad argument error on Git for Windows. If you’ve recently updated Git for Windows or switched to a new terminal environment, you might have run into this frustrating error: When Git triggers this, it’s almost never because
where git where curl If you see paths like C:\Program Files\Git\cmd\git.exe and also C:\Users\you\AppData\Local\GitHub\PortableGit... , reorder PATH so the official Git for Windows appears first. To confirm it’s not just Git, run: Broken or missing SSL/TLS backend Git for Windows
curl 8.4.0 (Windows) libcurl/8.4.0 Schannel or Conflicting http