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00956: Troubleshooting FLEXlm error -12 on TCP/IP networks


Troubleshooting FLEXlm error -12 on TCP/IP networks


A FLEXlm error -12 is an indication of TCP/IP network issue on the client side. It is possible that other workstations can successfully check out a license. 

Here is additional information from Globetrotter on the definition of a FLEXlm error -12: 

-12 LM_BADCOMM “invalid returned data from license server” 
The port number returned from lmgrd is invalid. 
An attempted connection to a vendor daemon did not result in a correct acknowledgment from the daemon.The daemon did not send back a message within the timeout intervalA message from the daemon had an invalid checksum. 
An lc_userlist() request did not receive the correct data. 


Here is list of items to check and possible solutions. 

1. Are you able to ping the server running the BLM (BASIS License Manager) by name? 
* Verify that the local PC’s HOSTS file has a correct entry for the server’s ip address and name. 
* Verify under Windows that the HOSTS file is in the correct directory and does not have any file extension such HOSTS.SAM or HOSTS.TXT 
* If using DNS or WINS, confirm that DNS or WINS are configured correctly and they have reverse name lookup. Try disabling DNS or WINS and adding a HOSTS file. 

2. Verify all current Windows Service packs have been loaded. 

3. Re-install TCP/IP. The easiest way to do this is to remove all Network configuration information and then reboot the Workstation. After rebooting, set up the netowrk configuration information again and reboot again. 

4. Install the latest drivers for NIC cards. Check NIC card settings for connection type – on one site selecting the correct connector type solved the issue. We have also seen using onboard network cards result in FLEXlm 12 – disabling these onboard NIC cards n the BIOS and then reinstalling PCI network cards resolved the issue on one site. 

5. Confirm IPCONFIG information is correct. 

6. It may be possible that the client is running out of sockets on the workstation. At a DOS prompt, type netstat -a to see if they are running out of sockets. They may be running older TSR applications, or using soft firewalls and either or both of these may be using up all the sockets. 

7. Check for firewall software loaded on the PC. If disabled, does the error still occur? 

8. We have seen some virus dectection software also cause this behavior. Be sure that virus detecting was turned off during the install in addition to turning it off to see if the FLEXlm -12 error goes away. If it does, then this software is somehow interfering with the way TCP/IP communicates. 

9. Reload the Windows operating system. Globetrotter has suggested to do this as there may be older system DLLs. 

10. At one site enabling and correctly configuring MS Proxy on the workstations eliminated the error. Also, if MS Proxy is disabled but still installed it can cause problems. Either remove it completely or configure it to properly work. 

11. It’s possible that the Network card Driver file has been corrupted and needs to be replaced with either the current driver file availble from the supplier, or perhaps replacing the current driver file with one that is known to be ‘good’ (from another machine) may also help.

Last Modified: 11/16/2004 Product: License Manager Operating System: Windows Error Number: -12

BASIS structures five components of their technology into the BBx Generations.

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