I've coem across the "No Database " error before and to my knowledge the only way to correct it was to do a reinstall.
fwiw The error started happening after some Windows updates
maybe someone else has more info
It seems strange that a Windows update would cause that problem. It isn't one that I've noticed.
It seems more likely that it is a problem with the Autodesk installation process. Since installing Civil-3D 2007, I periodically have had the Installation Wizard pop open and tell me to insert the Civil-3D disk when I'm doing something that has absolutely no relation to any Autodesk product. That indicates to me that something is being done incorrectly by Autodesk (big surprise).
Autodesk never has seemed to figure out the Windows installation process. Autodesk software is the only software I own where uninstalling one piece of Autodesk software breaks EVERY SINGLE OTHER PIECE of Autodesk software on the system. Autodesk seems to think this is normal and to be expected, but it's really a sign that something is WRONG.