"License of Rhinoceros Is Already in Use" Warning

No longer supported
Zoo 4.0 was the license manager for Rhino 4, which reached end of life long ago. This article is kept for historical reference. For current LAN Zoo licensing, see the LAN Zoo guide.

Question

When I launch Rhino 4.0, I get the following error:

This license of Rhinoceros is already in use on <COMPUTER NAME>.

Answer

You can receive this message if:

  1. The same Rhino 4.0 CD-Key was used to install Rhino on more than one workstation.
  2. One of the Rhino 4.0 CD-Keys you added to your Zoo 4.0 server was also used during a stand-alone node installation.

If all of the workstations are supposed to be running as workgroup (or network) nodes, which obtain their licenses from a Zoo 4.0 at run time, then you can solve this problem by following these steps:

  1. Launch Rhino 4.0.
  2. Click Help → About Rhinoceros.
  3. If the About dialog box reports that its license is a stand-alone node, then:
    1. Close Rhino and restart Rhino by running it as an administrator.
    2. Click Tools → License Manager → Workgroup Node.
    3. Close Rhino.

When you start Rhino again, it will be running as a workgroup node.