FLEXlm Error: Cannot read data from license server (-16,287)

Last Published: April 25, 2020

Error Message

When attempting to start ArcGIS, the license manager returns the following error:

"FLEXlm Error: Cannot read data from license server
The license server process appears to be running, but is not responding.
If this persists, notify the System Administrator.
(The lmgrd and vendor daemon processes should be terminated and
Feature: ARC/INFO
Hostname: <computer>
License path:
FLEXlm error: -16,287"


The license manager cannot read data from the ESRI daemon within the timeout interval.

Solution or Workaround

Below is a list of possible solutions arranged by most to least common.
The instructions below include making changes to essential parts of your operating system. It is recommended that you backup your operating system and files, including the registry, before proceeding. Consult with a qualified computer systems professional, if necessary.

Esri cannot guarantee results from incorrect modifications while following these instructions; therefore, use caution and proceed at your own risk.
  • Check that the key TcpMaxConnectRetransmissions was created in the registry under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters. Ensure that the value is 0. Also check that it was created in the folder 'Parameters' not 'Parameter'.

    If TcpMaxConnectRetransmissions does not exist in 'Parameters', create it as a new DWORD value. The location will be HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters. Set the value to 0.
  • Release the lockESRI file.
    1. Navigate to Start > Programs > ArcGIS > License Manager > License Manager Tools.
    2. Select the Configuration using Services radio button and then make sure that the 'ESRI License Manager' or 'ArcGIS License Manager' is highlighted in the box below.
    3. Click the Start/Stop/Reread tab.
    4. Click the Stop Server button. The message will display 'Server Stopping' and will not change.
    5. Start Windows Explorer and browse to C:\flexlm.
    6. Delete the contents of C:\flexlm.
    7. Back in LMTOOLS, click the Start Server button. The message displays 'Starting Server' and does not change.

Article ID:000004855

  • ArcMap 8 x
  • ArcMap 9 x
  • Legacy Products

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