Hello!

Let me first tell you what I know about the behavior of the Ansys licensing. 

Ansys licenses assign your machine to the license via a network connection ID. Putting the machine to sleep or changing to a different network like VPN with Opticstudio open, then opening ab additional instance assigns another license seat, since it it is considered a "new"connection. That results in a "stuck" extra license being left over on the server (which clears automatically in 2 hours). So your license should be available soon automaticallu.

There is a bug report open to improive the behavior of licenses in the future when swittching networks and lower the server timeout. If you want to be notified when this is changed, pelase open a support ticket on Zemax.com 

In the meantime, here are the available workarounds. 

Mitigation steps on the client machines

1 - When you get that "a licenses in use" error, close all instances of Opticstudio and open a fresh one (or more than one if needed). That generally releases all seats assigned to your machine.

2 - Avoid the issue - Save and close OpticStudio before putting a machine to sleep, before  connecting to a VPN, before disconnecting from a network or before moving a machine to another location / network connection. That allows Opticstudio to close the session on the server gracefully.  

3 - Work "offline" - You may also have better luck using the "borrow" feature. This pulls the license seat off the server to use offline. Close Opticstudio, then borrow a seat and open as many instances as you may need. 

https://support.zemax.com/hc/en-us/articles/12705804352659-Borrowing-an-Ansys-network-license-for-offline-use-with-Zemax-applications- 

Server options (for those with access to the license server at your organization). 

1 -  There is an option to set a lower timeout to automatically clear "stuck" licenses like this. The default is 2 hours, and it can only be set to a minimum of 1 hour unfortunately. Here's how to do it: https://install.simutechgroup.com/how-to-modify-the-license-timeout-setting-in-options-file

2 -Stop / start the Ansys License Manager. This will delete all "stuck" seats but has the side effect of disconnecting everyone for a minute or so. But if most people aree down its a quick option to do. ,   https://install.simutechgroup.com/1013561-how-to-restart-the-license-server

3 - Clearing "stuck" license users from the license server. See the article below. Note that the features for Opticstrudio are zos_level1 zos_level2 and / or zos_level3 (pro premium, enterprise, depending on what you purchased) instead of the lumerical features it talks about. 

https://optics.ansys.com/hc/en-us/articles/5772157750675

Thanks for the response Don. 
I will open a case to track the bug. 

Best 

Kaleb  

I am trying to open a case to be notified about this bug so I can know as soon as possible when there is a solution. We are forced to restart our Zemax server minimum once a day to get rid of stuck licenses so it is high importance to us. 

When I try to open a case button is grayed out. 
I am an end user of a license, but apparently the end user count still says 0.
 

 Any reason for this? 
 

Looks like the end user count finally updated, but still cannot open a case.

Hello! 

“End users” arent used for Ansys licenses, we will be disabling that shortly. Normally those with an Ansys license can register for support from the login box on Zemax.com or at @ https://www.zemax.com/register-for-support

Please email zemax.support@ansys.com .That will open a case for you and I can mark you as supported as well. 

Hello all!

This is a known issue with Ansys FlexLM licenses when network is changed or a machine is put to sleep and woken up as the network ID changes when you reconnect. We have both an internal bug report on this, and Ansys is planning updates in future around this as well.  

At the moment, there is a new version of the Ansys License Manager available that reduces the timeout to 3 minutes previously 2 hours, so should help minimize downtime if your license gets “stuck” on the server after a network change / disconnect , machine sleep, or software crash .

The latest Windows release of the 2024 r1 License Manager is linked in the “Downloads” section of the activation article below. If your license server uses Linux then open a support case on Zemax.com and I can get your server admins in touch with Ansys to help. 

Important: This License manager version only needs to be installed on the license server, not any client machines running OpticStudio.

https://support.zemax.com/hc/en-us/articles/6621657653907-Ansys-Zemax-license-server-installation-and-activation