Old cached versions of formulas can point to dead links. Run brew update followed by brew doctor to ensure your local repository is healthy.
Sometimes the main QEMU package fails because a sub-resource is missing. For example, if using virt-manager , installing qemu-block-gluster separately can fix initialization failures. failed to download resource qemu
In Linux environments, "failed to download resource" usually indicates a broken package dependency or a repository that needs refreshing. Old cached versions of formulas can point to dead links
If your network has unstable IPv6 support, package managers may fail to reach mirror servers. Temporarily disabling IPv6 can force the download through IPv4. 3. Fix for Android Studio (AVD) if using virt-manager