CFD 2021 single-user license error ‘The motion solver license could not be checked out from the license server’


Running an analysis in CFD 2021 results in this error:

The (motion) Solver license could not be checked out from the license server

A single-user license is assigned to the user and available under Licensing:


The Autodesk Desktop Licensing Service update version causes this error.

To verify the installed Licensing Service version on your system open this file in Notepad:

C:\Program Files (x86)\Common Files\Autodesk Shared\AdskLicensing\version.ini

For example:


1. Install the latest Autodesk Desktop Licensing Service, currently version

You can uninstall all the previous licensing updates by running this file C:\Program Files (x86)\Common Files\Autodesk Shared\AdskLicensing\uninstall.exe.

Once the folder is empty run the latest licensing service from the link above.

2. Install the latest Autodesk Single Sign-On update as well:


The Autodesk knowledge base reference article explaining the cause of the error:

About the Author

Joanna Gryszka

Manufacturing Technical Support Specialist<br><br>Joanna has over eight years of experience working with Autodesk products. She started supporting core AutoCAD and network installations of all Autodesk products. She now has five years of experience with Inventor. <br> She graduated from Mechanical Engineering and has been providing solutions to clients and dedicating her knowledge to the Solution Center since then.

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