Why does Windows 10 refuse to install certain drivers?

Windows 10 often refuses drivers because they're not digitally signed or Windows detects an incompatibility with your specific system version. It can also come from a conflict with an old driver still hanging around, or Windows thinks the one you're trying to install is older than the one already in place. Before forcing the installation, I'd recommend checking Device Manager to see if there's something conflicting, and if not, downloading directly from the manufacturer's website rather than looking on generic sites.

If the driver refuses to install, try disabling digital signature verification temporarily - that saved me once with an old USB device that Windows 10 was flatly refusing. Restart into diagnostic mode (F8 on startup), disable the signature, install your thing, then re-enable it. Otherwise, check if the driver is really compatible with your exact Windows 10 build, because even a minor version can cause issues - Windows is picky about that.

I struggled with that on an old network printer, and what really helped me was checking if the driver was compatible with your machine's architecture (32 or 64 bit) - a lot of people forget that and download the wrong version. Also try forcing the installation in safe mode, sometimes Windows is less picky about signatures in that state, or check the installation logs (you can find them in Device Manager by right-clicking the device > Properties > Driver tab > Details) to see the exact error instead of just guessing in the dark.