ORA-12537:Tns connection Closed in Toad


ORA-12537 TNS:connection closed


* In the Sqlnet.ora file the parameter TCP.VALIDNODE_CHECKING is enabled and TCP.INVITEDNODES is set to some specific IP’s of the Client Machine.


Comment the following line in sqlnet.ora and  try again or restart the listener

          tcp.validnode_checking = yes

  • January 4, 2018 | 15 views
  • Comments