Windows 11 KB5066835 is causing the following issues: a bug that blocks lockhost connection, File Explorer preview pane and ...

Update 10/17/25: Microsoft fixes the bug using a KIR (Known Issue Rollback) update. More information added to end of story. Microsoft's October Windows 11 updates have broken the "localhost" ...

Microsoft's timing is awkward, as it continues to encourage Windows 10 users to upgrade now that official support has ended.

If you encounter the Localhost refused to connect error message when running any web server on your local Windows 11/10 computer, then this post is intended to help ...