Hello,
Thank you for your message.
Could you please clarify if I'm right in assuming that you use the Windows security authorization method in order to establish an Internet-ID connection to the remote Host?
If this is the case, please double-check that you have set required permissions and added Windows users in the Host settings as described in
this guide on setting up the Windows security authorization method.
In addition, please clarify which authorization method is selected in the Connection properties - Authorization tab on the Viewer's side:

And last but not least, please double-check that the credentials you're entering in order to login to the remote Host are the same credentials that are set in the Host settings - namely, that you enter the correct Windows username and the password that is usually used for this Windows user to login on the Host machine (please note, that perhaps it's not the same password that was set as a
Single password for the Host).
Hope that helps.