Troubleshooting on FLEXlm License Manager Error: "Vendor daemon can't talk to lmgrd"

Problem

Start Flexlm license manager by clicking "Start" button few times but the prompt "License....can not start" is still there. Closed license manager, then re-open it, the License manager is running some how, button "Stop" appear.

From task manager, I see the process "LMGRD.exe"(Service of license manager) is running. After waiting for a moment, INTEL.exe just start/stop (appeared / deleted) rapidly. After a little more, LMGRD.exe is disappeared too.

From license server log, found below error message after license manager started:

11:35:36 (lmgrd) Starting vendor daemons ...
11:35:36 (lmgrd) License server manager (lmgrd) startup failed:
11:35:36 (lmgrd) File not found, 28000
11:35:36 (lmgrd) Started INTEL (pid 11396)
11:35:36 (INTEL) FlexNet Licensing version v11.12.0.0 build 136775 x64_n6
...
11:35:39 (INTEL) Vendor daemon can't talk to lmgrd (Cannot connect to license server system. (-15,10:10061 "WinSock: Connection refused"))
11:35:39 (INTEL) EXITING DUE TO SIGNAL 28 Exit reason 5
11:35:41 (lmgrd) INTEL exited with status 28 (Communications error)

Firewall is already turned off.

Version

Windows 7

FlexNet Licensing v11.12.0.0

Solution

1. Stop the license service using LMTOOLS.EXE or in Windows Services.
2. Stop any process in Task Manager like lmgrd.exe and adskflex.exe (or whatever the vendor daemon is named).
3. Start the DEP program from Control Panel > System > Advanced > Performance Settings > Data Excution Prevention.
4. Add an exception for LMGRD.exe, INTEL.exe and possibly also LMUTIL.EXE, LMTOOLS.EXE where the license manager is installed. Or you may select turn off DEP for all programs.