The issue occurrs due to firewall being disabled for Adobe Captivate (2019 release). To enable the firewall, use the netsh command in the command prompt.
Enter the command:
netsh advfirewall firewall add rule name="Adobe Captivate 2019 x64" dir=in action=allow program="C:\Program Files\Adobe\Adobe Captivate 2019 x64\AdobeCaptivate.exe" enable=yes
The command above sometimes does not work as expected if the Windows Firewall service is not up and running.
To enable the service, type services.msc in Windows > Run. In the list of services, manually start the “Windows Firewall” service, if not already started, and then run the command.
Restart the Captivate installation.
After you've got Adobe Captivate up and running, we recommend that you update Captivate to the latest update. For more information, see Captivate (2019 release) Update 1 release notes.