Sometimes Automation jobs might fail when running through "Spotfire.Dxp.Automation.ClientJobSender.exe" whereas Automation Services Job would be working fine when executed through Automation Services Job Builder tool (Spotfire Analyst > Tools)  locally or on Server. More details about ClientJobSender can be found here
When Automation Job does not execute successfully through "Spotfire.Dxp.Automation.ClientJobSender.exe" then below error can be seen in the "Spotfire.Dxp.Automation.ClientJobSender.log" file which would be present in the same folder where "Spotfire.Dxp.Automation.ClientJobSender.exe" is placed. More details about "Spotfire.Dxp.Automation.ClientJobSender.log" can be found here

Error;20-01-21 14:56:04.916;7660;Console;Error executing job:
Error;20-01-21 14:56:04.916;7660;Console;System.Net.WebException: The request was aborted: Could not create SSL/TLS secure channel.    
at System.Net.HttpWebRequest.GetResponse()    
at Spotfire.Dxp.Automation.ClientJobSender.ServerConnectionManager.ReadManifestInformation()    
at Spotfire.Dxp.Automation.ClientJobSender.ServerConnectionManager.Connect(Uri serverUri, Int32 webServiceRequestTimoutSeconds)    
at Spotfire.Dxp.Automation.ClientJobSender.JobServiceHandler.Create(CommandLineManager cmd, Int32 webServiceRequestTimoutSeconds, String serverUrl)    
at Spotfire.Dxp.Automation.ClientJobSender.JobExecutionHandler.Run(CommandLineManager cmd)
Info;20-01-21 14:56:04.916:13.599;13652;Program;Starting application using command line 'https://spotfire-test.com C:\spotfireTest\Test1\test.xml'
Info;20-01-21 14:56:04.916.613;13652;Console;Connecting to server https://spotfire-test.com.
 

• https://docs.tibco.com/pub/spotfire_server/10.3.6/doc/html/TIB_sfire_autsvcs_UserGuide/GUID-4AA5222D-3EF1-4700-A28B-0120A5B9E42F.html

• https://docs.tibco.com/pub/spotfire_server/10.3.6/doc/html/TIB_sfire_autsvcs_UserGuide/GUID-4883AB93-57F1-45B7-BBB0-5836A0B386F1.html