How to fix “SOLIDWORKS cannot connect to license server” error

You’ve just set up the SolidNetWork License (SNL) manager and you see the licenses available on the server, but the client machine fails to obtain the license when opening the product. You see an error message “SOLIDWORKS cannot connect to license server” that looks like the one below or a similar variation.

SOLIDWORKS Cannot Connect

Why SOLIDWORKS cannot connect to license server

If you’ve confirmed that the SNL manager is the same version year on both the server and client machines, then the problem may be coming from the Windows firewall.

The SNL manager communicates across ports 25734 and 25735 to ensure that SOLIDWORKS products can obtain a license. Sometimes your Windows firewall may be blocking communication across these ports, so the solution is as easy as adding an inbound and outbound port exception.

Most of the time, setting up port exceptions from the server machine will be enough, however, there are times when the steps may need to be done on the client side as well. It is never a bad idea to set up these port exceptions, but to test whether the firewall may be the issue before setting up the exceptions you can try disabling your firewall to see if that makes a difference.

If the problem is resolved when disabling the firewall then setting up the port exceptions should resolve the issue, turn the firewall back on and set up the port exceptions. If the problem persists with the firewall disabled then the communication may be blocked by something outside of the firewall.

Users can follow the steps below to set up an inbound and outbound port exception to unblock the SNL manager from the Windows firewall.

Setting up port exceptions for the SNL

1. On the server machine, select Start menu and search for Windows Defender Firewall.
   

   Windows defender firewall

2. In the left pane, select the “Advance settings” link.

Windows Defender Firewall Advanced Settings

3. Select “Inbound Rules” and choose “New Rule.”
   

   Inbound rules

4. Select “Port” and click the “Next” button.
   

   New Inbound rule wizard

5. Make sure “TCP” is selected. Then, type “25734, 25735” (without quotation marks) for the “Specific local ports” field and click the “Next” button.
   

   Specific local ports

6. Select “Allow the connection” and then click the “Next” button.
   

   Action step: allow the connection

7. Select the desired profile to apply the exception. (Select all the profiles if unsure.)
   

   Choose profile to apply

8. Enter a name for the rule and click on the “Finish” button.
   

   Final new inbound rule step – name and finish

9. Repeat steps 3-8 for Outbound Rules as well

Additional ports to consider adding for other products can be found here:

• SQL Server – Port 1433 TCP
• SQL Server – Port 1434 TCP and UDP
• PDM Archive Sever – Port 3030 TCP and UDP
• PDM Web2 Server – Port 80 TCP
• PDM Web2 Server – Port 443 TCP
• Electrical Collaborative Server – Port 26666-26672 TCP

NOTE: multiple ports can be entered in step 5 if you have additional ports to unblock (e.g., “25734,25735, 1433, 1434, 3030”).

If you’re an active client on subscription and you’re still having trouble connecting to the license manager, reach out to our support team for additional help!