Unable to launch Fast Data Masker (FDM)
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Unable to launch Fast Data Masker (FDM)


Article ID: 190992


Updated On:


CA Test Data Manager (Data Finder / Grid Tools)


We are unable to launch the FDM User Interface, after upgrading to version 4.8. No error is thrown, so we aren't sure how to troubleshoot the issue.


Release : 4.8

Component : CA Test Data Manager


If you are attempting to launch FDM from the desktop icon, makes sure the path to the GTMapper.exe is correct and you are running as administrator privileges. By default, the path should be "C:\Program Files\Grid-Tools\FastDataMasker\GTMAPPER.exe". If the path is correct, and you're not seeing any errors thrown, try running FDM from the command line.

To run FDM from the command line:
  1. Open a command line prompt 
  2. cd C:\Program Files\Grid-Tools\FastDatamasker 
  3. Run the following command:   java –jar GTMAPPER.exe > %TEMP%\fdm.log 2>&1
  4. Look at the fdm.log to see what errors are recorded.


In this case the fdm.log created by attempting to start FDM via the command line, recorded the following error:
Error: Could not find or load main class –jar

There could be two possible issues causing this error.
  1. Something is wrong with the Java Installation.
  2. Something is wrong with the FDM Installation.

If FDM is installed on the same system as the other TDM Components, then the installation should have set the JAVA_HOME variable to use the OpenJDK release of Java that is shipped with TDM, which by default is:
JAVA_HOME=C:\Program Files\AdoptOpenJDK\jre-\

 Verify the version of Java the system is running. If there are more than one version of Java installed, the system could be picking up a different release, that is not compatible wit the FDM UI. To verify the Java version, open a command line and run: java -version. You should see the system using the version of Java installed by TDM:
C:\Windows\system32>java -version
openjdk version "1.8.0_212"
OpenJDK Runtime Environment (AdoptOpenJDK)(build 1.8.0_212-b04)
OpenJDK 64-Bit Server VM (AdoptOpenJDK)(build 25.212-b04, mixed mode)

If Java checks out, then the FDM installation is probably corrupt. Open a Support case and request the latest release of FDM. Since FDM is not tied to any particular TDM release, it is safe to install the lates release of FDM, regardless of your TDM version. 

In this case, patching FDM resolved the issue.