Overview
This error is caused when the remote site is refusing the connection. However, this could also be caused by Authentication Redirection settings.
Specifically, if you are redirecting allowed requests, this can cause this issue..
Investigating
To determine if this is the cause, navigate to the pre-authentication Group, and select the Authentication Redirect tab, and the Redirect From Group subtab.
Next, check to see if you have the Redirect Allowed Requests option selected. If it is selected, you can test by disabling this feature and retrying the connection to the remote website.
If that resolves the issue, you should consider leaving the Redirect Allowed Requests setting disabled, blocking all categories for the pre-authentication group, and maintaining a Local List of sites that you wish to bypass authentication for.
Please contact Netsweeper Support by emailing support@netsweeper.com, or review our Authentication Redirection documentation for more information