One issue with many downloads is the disk image is too small (default 20GB). If you just run qemu-img resize , Windows will not see the extra space.

There are no official, pre-made "fixed" Windows 10 QCOW2 images provided directly by Microsoft. For virtualization (e.g., KVM, Proxmox, or QEMU), the standard and most secure method is to download the official Windows 10 ISO and manually create your own QCOW2 image.

If you must download a pre-configured image, look for those that specifically state they include or VirtIO pre-installed:

Pre-allocated Qcow2 reduces metadata overhead:

The “fixed” solution is a methodology. By using the conversion techniques, virt-builder , and the repair commands outlined in this guide, you will never be at the mercy of a broken download again. You become the fix.