Resolving "Unable to communicate with license manager" Errors

Summary: Tips for resolving the dreaded “Unable to communicate with license manager” error.

Updated: Jan 12, 2010

A new reason has been determined that can also cause this error when running Rhino V4 under Vista or Windows 7. It has to do with a conflict with User Account Control. Right-mouse click on the Rhino V4 icon, and select Run as Administrator. If this solves the problem, then be sure to download and install Rhino V4 Service Release 7. Installing SR7 should fix the problem. -JB

Updated: May 21, 2008

When you run either Rhino 3.0 or Rhino 4.0, you receive the following error message:

The “Unable to communicate with license manager” message is caused by Rhino's inability to communicate with its license manager module listed below. This error can occur in either Standalone and Workgroup Node installations.

This error is due to one of the following situations:

1. Missing license manager files.
2. Missing Windows System Registry entries.
3. Missing runtime library support files.
4. Windows Registry security issue.

To get to the current service release .

A new reason has been determined that can also cause this error when running Rhino V4 under Vista or Windows 7. It has to do with a conflict with User Account Control. Right-mouse click on the Rhino V4 icon, and select Run as Administrator. If this solves the problem, then be sure to download and install Rhino V4 Service Release 7. Installing SR7 should fix the problem.

On English-language versions of Rhino, the license managment modules are located in the following folder:

 C:\Program Files\Common Files\McNeel Shared\License Manager

Rhino 3.0 and Rhino 4.0 use different license management modules:

• The Rhino 3.0 license manager is named McNeelLM.exe.
• The Rhino 4.0 license manager is named RhinoLM.exe.

If the license manager module for the version of Rhino that you are using does not exist, then you will need to re-install Rhino from your CD.

If the license manager module for the version of Rhino that you are using is present, then the module might not be registered - there might not be information in the Windows Registry that allows Rhino to locate this module. To solve this issue:

1. Make sure you are logged into your workstation as the Administrator or an equivalent user.
2. Make sure to disable virus detectors and anti-spyware agents.
3. Using Explorer, navigate to the above mentioned folder. (C:\Program Files\Common Files\McNeel Shared\License Manager)

If the error occurs when trying to run Rhino 3.0, then:

1. Download and unzip this batch file in the same folder as McNeelLM.exe.
2. Double-click on the Register_McNeelLM.bat batch file.
3. Windows Vista users: right-click on the file and select “Run as administrator”.

The batch file will echo the results to the command line, thus verifying success or failure. To confirm this method resolved the problem, run Rhino 3.0.

If the error occurs when trying to run Rhino 4.0, then:

1. Download and unzip this batch file in the same folder as RhinoLM.exe.
2. Double-click on the Register_RhinoLM.bat batch file.
3. Windows Vista users: right-click on the file and select “Run as administrator”.

The batch file will echo the results to the command line, thus verifying success or failure. To confirm this method resolved the problem, run Rhino 4.0.

If running the above batch file returns an error, then download and install the latest Microsoft runtime libraries and try again.

If the license manager module for the version of Rhino that you are using is present and the module us registered - you might not have enough rights to read the Windows Registry.

Run Regedit.exe. When open, find the RhinoLicenseManager.RhinoLicense key in HKEY_CLASSES_ROOT. For example:

Right-click on the key (in the left pane) and pick “Permissions…” from the context menu. For example:

Administrators should have Full Control and Read checked (under the Allow column) and Users should have Read checked. If this is not the case, then the users permissions have been modified, which is causing Rhino to not be able to read this key. Registry permissions issues are often caused by security policies have been pushed down onto the workstations that are members of an Active Directory domain. But, they have been known to have been caused by Windows Updates as well.

To set the permissions, navigate to the top of the hive (HKEY_CLASSES_ROOT) and try to set the proper permissions from there. In doing this, all keys below this hive will inherit the permissions (and hopefully the problem will be solved). If you are unable to do this, then you will need to contact your computer support staff and ask for assistance.

Another solution, for Windows Vista users, is to turn off User Account Control.