MinGW 6.3.0 is a legacy version. If your project does not strictly require this specific version, consider using more modern and reliable distributions:
The primary reason for this error is that the automated setup cannot reach the SourceForge repository mirrors used by the installer. Many "official" installers point to legacy links that are no longer maintained, or the connection is interrupted by strict antivirus and firewall settings . Step-by-Step Fix: Manual Installation
Under , find the Path variable and click Edit .