First scan worked fine; subsequent ones return Error 5

[Thomas]

Chances are Device Doctor might have been blocked by your security software from accessing the internet?

If that will not be possible to resolve (most probably by granting full internet rights for Device Doctor in your firewall, though some other types of security applications also might go in the way), it shall still be possible to update: Device Doctor shall offer you to export the list of drivers to html file which you can then open in your web browser and download from there.