Why do I receive License Manager Error -8?

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Why do I receive "License Manager Error -8"?
License Manager Error -8.
License checkout failed. Encryption code in license file is inconsistent.

Accepted Answer

MathWorks Support Team
MathWorks Support Team on 26 Dec 2023
Edited: MathWorks Support Team on 26 Dec 2023
This issue generally indicates that the license file is served from the Network License Manager and that there is a problem with the license.dat file on the machine running the Network License Manager. The cause of this error may be due to one of the following:

Incorrect Host ID in license.dat file

It is possible that the Host ID for which the license.dat file was generated is not the Host ID of the machine hosting the Network License Manager. The first step is to locate the license file (license.dat) for the Network License Manager. The license.dat file on the server machine is located in:
Where $MATLABROOT is the MATLAB installation directory. For more details on finding this file, please refer to the following article:
Where are the license files for MATLAB located?
In the license file, make sure that the Host ID specified in the license file matches the Host ID on the "SERVER" line of the license file. The SERVER and DAEMON lines are added automatically when installing the Network License Manager with the MathWorks Product Installer. They can be added manually if you did not use the MathWorks Product Installer to install the Network License Manager.
The Host ID of the license file will be in a comment line in the license file. For example:
# BEGIN------cut here------CUT HERE-----BEGIN
# MATLAB license passcode file.
# LicenseNo: 123456 HostID: 001122334455
In this example, the Host ID is the MAC address 001122334455. This same MAC address should be in the SERVER line of the license file. For example:
SERVER my-license-host 001122334455 27000
NOTE: Changing the Host ID listed in the commented section of the license file will not resolve the error. If your Host ID is incorrect, you will need to obtain a new license file generated for the correct Host ID.

Missing, corrupt, or incorrect characters in license.dat file

This error may be the result of having extra carriage returns in your license file. In order to avoid this, ensure that the following strings all begin on a left justified line: #, SERVER, DAEMON, or INCREMENT. Sometimes an INCREMENT line can get wrapped on the end of the preceding INCREMENT line, causing it to be omitted.

Network license being used to activate MATLAB

It is also possible for this error to occur if a network license is attempting to be used in place of an Individual or Designated Computer license. If you are trying to activate MATLAB for a network license, you need either a license.dat or network.lic from the person who maintains the Network License Manager. If a Network License Manager has not already been setup, then it needs to be in order to use the license. Read more information from the link below about the differences between license files types:
What are the differences between the license.lic, license.dat, network.lic, and license_info.xml license files?

System time, date, or locale issue

This error can sometimes occur if the system time and date are not set properly. Check to make sure that the date and time are correctly set on the machine before proceeding.
If you are located in Turkey, or the default language of your computer is Turkish, please refer to the article below:
Why do I see license manager error -8 when launching MATLAB on Linux when my locale is set to Turkey?
  1 Comment
cui,xingxing on 13 May 2018
Edited: cui,xingxing on 13 May 2018
Not clear! my matlab version is R2017b,win10,64bit:
1,My .lic files don't have a SERVER line also.
2,my matlab install root do't have "license.dat" file
3,what is "license server machine"? Where and How can I find it?my matlab activation without internet.

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More Answers (1)

tingting jiang
tingting jiang on 28 Apr 2020
Edited: Walter Roberson on 28 Apr 2020
I don't understand the solution, and I don't know what's wrong. As a person who doesn't know much about computers, I hope to have a picture or video guide.
  1 Comment
Walter Roberson
Walter Roberson on 28 Apr 2020
I have tracked down three possible causes for this problem on MATLAB installations. All three of them are problems with remote license servers, and require that the license server administrator make changes. If you are someone who does not know much about computers, then you are not the license server administrator, so you should ask your license server adminstrator to repair the problem.
The one case that I tracked down that involves something on the user's machine, involves cases where the user is using a cracked version of MATLAB. People who are running cracked versions of MATLAB should purchase MATLAB.

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