"Unable to execute the tool" error

I saw a similar thread, but it was unrelated so I'm starting a new one.

Using AutoCAD Civil 3D 2009, trying to access the tool palettes for roadway corridor assemblies. The TP will load correctly, and the images/text on the pallet are there, but when I try to drag an entity from the pallet into the drawing, I am getting the following message:

Unable to execute the tool. Possible Causes are:

- Tool is not registered properly...

- Tool is from another application...

The first thing I did was try to reload the profile and make sure there wasn't a problem there, and that didn't fix the problem. I've checked my paths and everything seems to be pointing to the right places. Since the pallet itself loads, i don't think the problem is with paths, but i don't know for sure. These pallets are the default imperial roadways that came with C3D so i don't think the problem is related to application incompatibility, so I'm wondering if it has to do with the tool not being registered properly.

How do I check this? How do I register a tool, or troubleshoot registration errors?

Has anyone had this problem before or have any other ideas on how to fix it?

Is there a RegisteredTools folder for Civil 3D? If so what's in it or is it completely empty?

There are two files:

ADTMtlStockTools.atc and C3DStockTools.atc

http://forums.autodesk.com/t5/AutoCAD-Civil-3D/Tool-Palettes-problems-Class-not-registered/m-p/2308357

Here I found a way which worked and solved the problem. In short: re-activate the secondary installer which installs the Autodesk product when a local user starts it for the first time. To achieve this delete the appropiate key from the registry and delete the appropiate directories and all its contents from the users Document and settings. All your custom settings will vanish unless you save those files and settings previously.