Error: "[-15.570.0] A valid license could not be obtained by the network license manager

Jan 8, 2015


You open an Autodesk product on the computer that contains the network license server and select Specify the License Server System in the FLEXnet License Finder dialog box, but the following error message is displayed:


You are missing the license for the product you are attempting to open

Your Autodesk Network License Manager (NLM) is installed on a Windows Server 2008 or Windows Vista/7 machine 

Your NLM and Autodesk product exist on the same workstation with IPv6 enabled.

Your Client system has an incorrect Date/Time (the server will reject license checkouts from clients that have a notable difference in date/time from the server)

Blocked port on license manager system


Verify and/or retrieve the proper license and make sure it is running in LMTOOLS

If your NLM and your Autodesk product are installed on the same workstation, verify that the connection made to the NLM is not via IPv6.  If it is, disable IPv6 or redirect the protocol to use IPv4 instead.

Method #1:  
To verify connectivity with your NLM server:
  1. Open a command prompt (Start > Run > CMD) and PING your server hostname:



A typical IPv6 response for localhost loopback when the NLM is on the same machine may be one of the following:
  • ::1 
  • a full IPv6 address such as 3ffe:1900:4545:3:200:f8ff:fe21:67cf
Your results may look different.  
  1. If the response is an IPv6 as in the example above, you need to disable IPv6 on your Network LAN settings and verify PING again to ensure it has an IPv4 address in the format of  
For more configuration changes, continue on to Method #2.


Method #2

If you are unable to disable IPv6 or need IPv6 on your network, change your system HOSTS file to redirect the protocol to use an IPv4 address instead. 
  1. Verify that connectivity to the NLM server is using IPv6, as described in Method #1.  
If your response is an IPv6, you need to edit your HOSTS file to point the server hostname to an IPv4 address instead.  You need Administrative rights for this process. 
—First ensure that the User Account Control (UAC) in Windows is disabled.  Open the Control Panel and choose System and Security:



Then choose Change User Account Control settings:




Finally, disable the UAC option by setting it to Never notify:





Now you should be able to open and edit the Windows HOSTS file to make the necessary changes. 


  1. Find the file in the following location:


  1. Open the hosts file with Notepad.  You should have Administrator privileges when performing this task. 
  2. If the file is Read-only, you may need to make the file writable from within the file properties dialog box. 
Your HOSTS file should appear similar to the image below. 

If your NLM and Autodesk product are on the same machine:
  1. Comment out the IPv6 localhost address of ::1 by adding a # sign. 
  2. Add your hostname behind the IPv4 localhost address as shown. 
  3. Save the file and close Notepad. 



If your NLM is on a different server than your client installed software:

  1.  Create a new entry for your NLM server with the correct IPv4 formatted address followed by your server hostname and save the file then close Notepad. 
  2. Verify IPv4 connectivity by opening the Command prompt and PING the server hostname.  It should now read the appropriate IPv4 response.  If your NLM is local, it should read  If the NLM is on a server, it should read the IP address of your server. 




  1. When you launch your Autodesk product, it should launch and obtain a license as appropriate. 

It is possible that a port is blocked on the machine housing the License Server. In this case we can force the CLIENT machine to use a different port.
  1. Right-click the My Computer icon.
  2. Click the Advanced tab.
  3. Click "Environment Variables".
  4. Under the System Variables window, click "New".
  5. In the Variable name field enter ADSKFLEX_LICENSE_FILE
  6. In the Variable value field enter 27000@YOUR_SERVER_NAME _OR _IP
  7. Click "Okay" and test


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