What the FFmpeg certificate failure establishes
The reported configure step fails to download FFmpeg and prints a certificate verification error. This establishes that a download did not complete under that configuration. It does not show that the game, graphics driver or relinker is incompatible.
Comments also show users retrying a certificate command without checking whether the referenced file exists. A path from another Git installation may point at the wrong directory on your computer.
1. Identify the actual CMake and certificate file
Record the CMake version and executable path, the exact URL printed in the failure, and any proxy or enterprise certificate context. Check the file on your machine before setting a certificate variable.
Get-Command cmake | Select-Object Name,Source
cmake --version
Get-Item Env:CMAKE_TLS_CAINFO,Env:SSL_CERT_FILE -ErrorAction SilentlyContinue
Test-Path "C:\Program Files\Git\mingw64\etc\ssl\certs\ca-bundle.crt"A False result means that example path is absent; locate your actual trusted CA bundle instead. A successful environment-variable assignment normally prints no certificate and no success banner.
2. Keep PowerShell and Command Prompt syntax separate
After locating the correct trusted bundle, set it for the terminal in which you will rerun configuration. This illustrates the shell difference; the path below must exist on your machine.
PowerShell
$env:CMAKE_TLS_CAINFO = "C:\Program Files\Git\mingw64\etc\ssl\certs\ca-bundle.crt"
Test-Path $env:CMAKE_TLS_CAINFOCommand Prompt
set "CMAKE_TLS_CAINFO=C:\Program Files\Git\mingw64\etc\ssl\certs\ca-bundle.crt"
echo %CMAKE_TLS_CAINFO%The two syntaxes are not interchangeable. Do not assume a variable set in one terminal has appeared in another already-open terminal.
3. Reconfigure and inspect the same download
CMake documents CMAKE_TLS_CAINFO for its download operations. Check whether the project overrides download options, whether the endpoint redirects, and whether your proxy requires a separately trusted CA. Correct that trust chain rather than replacing complete project files from an unversioned archive.
Some comments suggest disabling verification. That changes the connection check and does not explain the original failure, so this checklist keeps it enabled. Match the actual project revision and CMake version before applying a workaround.
4. Record the outcome and continue the build
Success here means the intended dependency download verifies and CMake completes configuration and generation. The compiler and libraries targets must still finish separately. If the next error names libSPIRV.a, follow the missing-library page without assuming the certificate is still the cause.
For an upstream report, include the download URL, CMake version/path, the first configure error and the bundle location with private user information removed. Our source-build guide connects these checks to the full workflow. This page has not reproduced every commenter’s environment and does not promise one command resolves all certificate failures.
Sources
- CMake trusted CA bundle ↗
- CMake TLS verification ↗
- Upstream build requirements ↗
- Original FFmpeg error comment ↗
Prepare your next step.
Use the local tools alongside the upstream documentation.