
If you’re using USBTiny version 2 in Vista and having problems, try this driver signing tip from forum member grante – just keep in mind that it might be weird/risky… the hack that is, IT SEEMS A LITTLE SKETCHY – THIS IS A WARNING
Use this tool to sign the drivers with a test key and force windows to always boot in test mode. Works for me.
You can also try this – “Disable Driver Signing in Windows 7 Using Group Policy Editor“… we’ll try some/all of these out soon, for now – report back if you have anything to add!

Printable catalog (PDF)
“Signing with a test key” + “boot Windows in test mode” = standard procedure for testing kernel drivers.
That said, there is some incorrect information in the linked article.
Yes, 64-bit Vista and Win7 *require* signed drivers (and this requirement cannot be disabled), but 32-bit systems do not by default.
Also, the statement “…developers have to pay Microsoft to receive verified certificates…” is misleading. Yes, driver signing certificates *do* cost money, but they’re not purchased from Microsoft. There used to be a few places to get signing certs, but I think Verisign is the only source now. Unfortunately, they’re expensive ($499/year).
This onerous & expensive requirement effectively eliminates the possibility of creating open-source drivers for modern versions of Windows. Pity.
Comment by Keith — February 18, 2010 @ 1:50 am
I am running Windows 7 64 bit and had drivers loaded and working in a matter of minutes using the Driver Signature Enforcement Override tool mentioned above.
I had also tried setting the Group Policy to ignore unsigned drivers but this didn’t seem to work for me.
Comment by Mike Hankey — April 26, 2010 @ 3:48 pm