[JENKINS-58856] No Authorization Header for WinRM connection

I am trying to set up a Jenkins with Windows on-demand slaves.

The Windows EC2-Instances are started by the plugin, but the WinRM connection cannot be established. The logs are stuck in a "Waiting for WinRM to come up"-loop.

But I can create a WinRM-connection to the instances manually using a python library. When I compare both (the connection attempt by the EC2-Plugin and the connection by the lython tool) I observe the following:

• the POST-request to /wsman is answered with a 401 by the Windows instance


• this seems to be the case because the Authorization header is completely missing in the request

Is this a bug in the plugin or am I doing something wrong?

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Originally reported by christophniehoff, imported from: No Authorization Header for WinRM connection

• assignee: thoulen
  
• status: Open
  
• priority: Minor
  
• component(s): ec2-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 4
  
• imported: 2025-12-06
  

Raw content of original issue

I am trying to set up a Jenkins with Windows on-demand slaves.


The Windows EC2-Instances are started by the plugin, but the WinRM connection cannot be established. The logs are stuck in a "Waiting for WinRM to come up"-loop.


But I can create a WinRM-connection to the instances manually using a python library. When I compare both (the connection attempt by the EC2-Plugin and the connection by the lython tool) I observe the following:



	
the POST-request to /wsman is answered with a 401 by the Windows instance

	
this seems to be the case because the Authorization header is completely missing in the request



Is this a bug in the plugin or am I doing something wrong?

Start with the ec2-plugin's WinRM connection path and compare its POST request to /wsman with the working Python-library connection. Confirm whether the Authorization header is omitted, then verify that a Windows EC2 agent connects without the "Waiting for WinRM to come up" loop.

Written by the indexing model from the issue text.