LES Users getting the following error when launching the LES client. How to troubleshoot the error?

The above error indicates that the access to the database from the LES Client server has some issue. 

RDP to LES Client Server and check the following to address the issue:

1. Check the TNSNAMES.ORA file for the database connection settings and make a note of the TNS service name.
2. Verify the connection to database using SQLPLUS from the LES Client server.
3. Check the definition in the 'Target' field for the LES Client Shortcut and it includes the correct database service name. 

Eg: "C:\Program Files (x86)\VelQuest\Core\Bin\VQCore.exe" -orcl where orcl is the tns service name defined in the TNSNAMES.ORA file.