Agent Not Reachable in Desktop central

Agent Not Reachable in Desktop central

We have recently migrated the ME-DC Server to a new computer, we verified the old http:\\oldserver:8383 its diverting to the http:\\newserver8383 however when we tried to scan the agents its showing Agent not reachable. I have check the KB and its mentioned to Add the Port 8027 to communicate with Agent. Can you please explain the steps to do ?

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