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On the DualShield SSO login page, after entering the user's login name, an error "Connection Refused: connect" is returned
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CAUSE
This error means is typically caused by the fact that the SQL database server is not working.
If we check the das6.log file below
C:\Program Files\Deepnet DualShield\tomcat\logs\das6.log
then we should find an event similar to the one below:
RESOLUTION
Restart the SQL database service and make sure it is working properly.