Acquiring license key results in "Cannot read data from license server" error

Technote (troubleshooting)


Attempts to acquire a license key results in FLEXlm error -16 stating "Cannot read data from license server".


The full error message is:

Vendor daemon can't talk to lmgrd (Cannot read data from license server system. (-16,287))


This error normally occurs when you have the license server installed in a path of more than 32 characters on 64 bit Windows machines.

Diagnosing the problem

Example – Server line on the license file with error:

SERVER hostname DISK_SERIAL_NUM=555g9feb
VENDOR rational "C:\Program Files (x86)\Rational\common\rational.exe"
VENDOR ibmratl "C:\Program Files (x86)\Rational\common\ibmratl.exe"

Example – Server line on the license file without the error:

SERVER hostname DISK_SERIAL_NUM=555g9feb
VENDOR rational "C:\Program Files\Rational\common\rational.exe"
VENDOR ibmratl "C:\Program Files\Rational\common\ibmratl.exe"

Note: VENDOR lines may appear as DAEMON lines in older license files. 

Resolving the problem


There are two workarounds for this error:

  • Move the FLEXnet installation to a directory with a shorter path.
    Then stop and restart the license server.

  • Verify that the path to the license file in the lmtools points to only one file that includes the licenses. Verify that the path does not point to both permanent and temporary licenses. In this way you reduce the length of the path to the license file.

    Example: if you only use permanent keys
    1. Click Start > Programs > IBM Rational > License Tools (LMTOOLS) > Config Services

    2. Remove the path to the rational_server_temp.dat file

    3. Stop, Start, and Reread the server in LMTOOLS so your license server can read the license file properly.

Related information

Error after Status Enquiry: Cannot read data from licen
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Document information

More support for:

Rational License Key Server

Software version:

All Versions

Operating system(s):


Reference #:


Modified date:


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