WSUS Import The Underlying Connection Was Closed

Originally posted on https://www.virtualizationhowto.com by Brandon Lee on August 7, 2023.

Microsoft recently announced that the WSUS import updates feature in the WSUS console would no longer be used. Instead, admins need to use a PowerShell script provided by Microsoft to import updates into WSUS. However, in my recent testing of the script on a Windows Server 2022 server with WSUS installed, after following the steps exactly from the Microsoft KB, I received the error, “The underlying connection was closed: An unexpected error occurred on a send.” Let’s look at the error and the fix for this issue.

The error background

The error “wsus import the underlying connection was closed” often presents as an “unexpected error” in the WSUS server. This error usually indicates an issue with the underlying connection between the WSUS server and the remote host or the server and the internet. In other cases, this could be a symptom of a transport connection problem.

I ran into the error using the new import method detailed here: WSUS and the Microsoft Update Catalog | Microsoft Learn.

Microsoft has now deprecated the old way to import updates using Internet Explorer and ActiveX controls. For many reasons, this method is no longer supported or works due to the old technologies involved.

The KB linked above has the PowerShell script here:

.DESCRIPTION
This script takes user…