Applying a license update for Zemax software products (Zemax legacy)


This article tells how to update a Zemax license for all products and licenses that have a serial number starting with "L" or "T" such as L100000. This includes red and green USB licenses or legacy softkey licenses. It does not apply to Ansys issued licenses. 

Before proceeding, please read:

If you are using an Ansys issued license and a 2022 R2 or newer Zemax software version and have renewed, do not follow this article. You will receive a separate email with instructions. 

If you have a black USB license dongle (where the license serial number is 22000-40999), see this article.

You can identify your license type using the guide located here: How to identify your legacy Zemax license

This article assumes you have already received an email with an update code for a renewal or other license change. You will need access to the currently activated machine to perform the update.

If your licensed machine has internet access, continue to the below section. If it does not have internet, move to Update a license without internet.


Update a license with internet

When you renew your license technical support or subscription, add a license seat, or upgrade to a new edition of Opticstudio, you will be sent an email with your license serial number and an update code. The code will be bracketed in a format similar to [123-456-789-d34-e456]. 

Note: Most users will not need to manually use the code to update their licenses. All Zemax software released after August 2016 includes an semi-automatic update check; this check occurs once a day the first time your Zemax software is launched. This requires the licensed machine has internet access.  

To verify that an update has been applied or to manually apply an update, follow the instructions below.

  1. On the machine where the license is activated, open the Zemax License Manager (ZLM). You can open the Zemax License Manager from Windows Start Menu > Programs > Zemax Opticstudio (or Opticsbuilder or OpticsViewer) > Zemax License Manager.. If you are working on a network license keyserver, open Windows Start Menu > Programs > Zemax License Manager.  
  2. For ZLMs released May 2019 or later, navigate to Manage Licenses.
    For ZLMs released before May 2019, navigate to License Information.

  3. In the ZLM license list, Locate the license number for which you received an update email. Verify the "Update" option is not grayed out. 

    If "Update" is grayed out or if the license is not listed: This means you are not logged into the machine where the license is installed. This most often happens with a network license when you are not logged into the server machine where the license is activated.

    For network license updates, you can forward the update email to somebody with access to the license server. The server name is listed in the "License type and location" column under "hosted on" similar to the image below.

  4. If Update is not grayed out, press the "Refresh" button. This doesn't check for updates, but does verify if an update has already been retrieved.


  5. Check the license information to see if it matches the update email you received . For example if the support expiration date or the number of seats has changed. 

    If the information is correct, you are done! You may discard the update code, as it cannot be re-used.

    If the license information is not updated, proceed to Step 6.

  6.  Click Update next to the license you are updating, then enter the update code including brackets []  and click OK. It will automatically refresh when done to display the updated information.

  7. If the license information is updated properly, you may discard the update code, as it cannot be re-used.

    If you got an error message or otherwise has not updated, check the FAQ below first to see if it has a resolution your problem. If that still doesn't resolve your issue, move on to the "Update a license without internet" section below to request an offline update.

Update a license without internet

This section describes how to apply a license update on machines without access to the internet, or if the auto-update fails. Before getting started, you should note:

  • Updates need to be applied on the machine where the license is installed. For network licenses, this means you need to log in to the keyserver machine that hosts the license rather than an OpticStudio client machine. 

To apply an update to your license on a machine without internet access, follow the steps below. 

  1. Request the update file. Email with a subject of "Offline license update request: L1XXXXX" . Replace L1XXXXX with your actual license number or numbers (if updating multiple licenses).

  2. Within one business day, you will receive an email containing a .v2c file type attachment. Save the .v2c file to the machine where the license is currently activated. We recommend a convenient folder such as Documents or Downloads. 

  3. Open the Zemax License Manager on the licensed machine, normally located in the Windows Start menu under either the Zemax OpticStudio or Zemax License Manager folder. 

  4. Locate the license number that you received an update code for. Make sure the "Update" button is not grayed out, and move to step 5.

    If "Update" is grayed out or if the license is not listed: This means you are not logged into the machine where the license is installed. This most often happens with a network license when you are not logged into the machine where the license is activated. Forward the update email and .v2c file to someone with access to the server listed under "hosted on" in the "License type" column to apply the update. 

  5. Click Launch Sentinel Admin Control Center located on the Troubleshoot tab or at the top of the Zemax License Manager.
  1. Click on Update/Attach in the left-hand Options column. Click Choose File and locate the .v2c file you saved. Click Apply File, and you should get a short message saying the update was applied. If you receive any errors, see the Getting Help section below. 

    Note: You may delete the .v2c file we send you after following this procedure as it cannot be reused.

  2. Open the Zemax License Manager again to verify your updated license matches the information in the update email you received. If the license information still isn't updated, move to the Getting Help section below to see what to provide when contacting support.

Frequently asked questions

This section details some of the common questions that occur when updating softkey licenses.

I get an error when opening License Manager or applying an update code. What should I do? 


  1. Make sure the machine is connected to the internet. If not, follow the offline update procedure in this article instead.
  2. Verify the update has not already been applied. Open the "License Information" or "Manage Licenses" page in Zemax License Manager and click "Refresh" ,That will allow you to verify the support expiration date and any other changes against the update email you were sent. 
  3. Verify that you have included the brackets [] in the update code.
  4. Make sure you are updating the correct license number on the "Manage License" or "License Information" page.
  5. Make sure you are not on the "New license" or "New Key" page. You cannot use update codes for a new activation.
  6. If you continue to experience issues and are sure the license has not already updated, you can try the offline method.

If I update a network license while seats are in use or checked-out from the network, will there be any interruption? 

Any client machines using the network license will see the updated license information immediately. If you have any checked-out (offline) seats, they will not display the updated information until they are checked back into the license pool. Updating the license while they are in use will not interrupt client's use of the license. 

Getting help

If you receive any error messages while updating, contact or open a support ticket  from within your Zemax account profile page for further help. Please include:

  • Your license number (such as L000001)
  • Any error messages you received and whether you are doing an online or offline update.
  • A screen shot of the Sentinel Keys page located in the Sentinel Admin Control Center from the licensed machine.
  • A screen shot of the "View license" or "License Information" section of the Zemax License Manager application
Was this article helpful?
0 out of 0 found this helpful



Article is closed for comments.