Lenovo Software Help Center

webRDP cannot connect to workstations due to NLA


ActiveX and WebRDP clients cannot connect to Windows workstations.

Possible Errors:
  • The remote computer has ended the connection.
  • The server reset the connection.
  • Parameter(s) you provided caused an error.
  • The server requires that the client support Enhanced RDP Security with CredSSP.
  • Received an error connecting to: <CN_OF_WEBAPP>


Windows RDS has an option called Network Level Authentication under the Remote Desktop Connection settings.

When this option is checked then only RDP 6 or higher RDP clients can connect. This excludes the Microsoft ActiveX RDP control and the Java Proper RDP Client.

To connect using the webRDP HTML Client, you must pass the username, password, and domain as part of the initial connection/handshake.  NLA performs user authentication before actually completing a full RDS connection.  It basically tests the user's credentials to make sure they are valid before establishing an RDS connection.

This means that you cannot initiate a generic RDS connection to the login screen, requiring the user to then manually enter their credentials.  To setup a RDS application that brings up the Windows login requires disabling NLA on the host workstation/server.

To disable NLA on the workstation:
  1. Access the workstation's System Control Panel.
  2. Select Remote settings.
  3. Uncheck the box for Allow connections only from computers running Remote Desktop with Network Level Authentication (recommended).
  4. Click OK.

    • Related Articles

    • webRDP cannot connect to new Windows 10 workstations / Windows Server 2016 servers

      Issue The HTML5 webRDP client will not connect to new Windows 10 workstations, but will connect to Windows 7 or Windows 8 workstations. Possible Errors: Received an error connecting to: <CN_OF_WEBAPP> Solution Clean installations of Windows 10 now ...
    • webRDP HTML5 Gateway Received unexpected or empty packet

      This is caused by the server or workstation being set to only allow connections from computers running Remote Desktop with Network Level Authentication (NLA). webRDP does not support NLA.  Therefore, you will need to set the server or workstation to ...
    • Number of connections for webRDP Client

      Question: How many RDP connections can my users make, through Unified Workspace, using the webRDP client? Solution: As the webRDP client is very resource intensive, for the UW relay server, we've found that the each relay can handle approximately ...
    • webRDP HTML 5 client and it starts to connect and then terminates

      This is typically due to a network device like a load balancer or firewall that does not support webSockets. webSockets ( ws:// ) is a protocol proving full-duplex communications over a single TCP connection. It is used by Stoneware's webRDP HTML 5 ...
    • webRDP Java Client URL

      Question Is there a way to troubleshoot webRDP connections? Solution Customer's can download the webRDP.jar file from their cloud, to assist with troubleshooting webRDP connections. The jar can be downloaded ...
    • Popular Articles

    • Can a Teacher see Students outside of school?

      This content has moved! Visit the new LanSchool Classic Help Desk It looks like you may be interested in LanSchool Classic General FAQ.
    • LanSchool Latest Release Notes

      This content has moved! Visit the new LanSchool Classic Help Desk It looks like you may be interested in LanSchool Classic Latest Release Notes.
    • How to uninstall LanSchool Student and WebHelper from Chromebook

      This content has moved! Visit the new LanSchool Classic Help Desk It looks like you may be interested in Mass Deploying LanSchool Student for Chromebook.
    • LanSchool Release Notes

      LanSchool™ Release Notes Updated: December 16, 2019 Component Versions LanSchool, December 16, 2019 Chromebook App, December 16, 2019 Chrome Web Helper:, December 16, 2019iOS TA and Student 8.2.0, December 16, 2019 Android ...
    • Controlling multiple students at once

      Problem: Can I remote control multiple computers at once? Cause: N/A Prerequisite(s): LanSchool Teacher and Student Solution(s): If all of the computers in the lab are the same basic image or configuration (for example. all Windows XP machines with ...
    • Recent Articles

    • Lenovo Software Newsletter

      Question Is there a way I can be notified about product updates? Solution To receive updates from Lenovo Software about product updates, we encourage customers to subscribe to our Lenovo Software Newsletter.
    • Allow Help Desk to reset Image Challenge images

      Issue Customer would like to allow Help Desk users to only be able to reset user Image Challenge images when they have been forgotten by a user. Solution This can be done by assigning specific users in the system the User Group Admin role, as well as ...
    • Troubleshoot RDS

      This is a good article, from Microsoft, on how to troubleshoot RDS/RDP logon issues. https://social.technet.microsoft.com/wiki/contents/articles/37841.remote-desktop-services-rds-logon-connectivity-overview-and-troubleshooting.aspx
    • Building an Employee Phonebook system

      Building a Mini Application Post #20 Can it really be that simple to create a little application with Report and Form Builder?  This tutorial shows you that it is - and actually helps you make a useful application at the same time as learning how to ...
    • Working with Binary Data in Report Services

      Quick Start Guide - Binary Data This tutorial is designed as a quick "How Do I Work With Binary Data" tutorial.  It walks through the steps necessary to upload an image to a database.  Every webNetwork 6.0 installation ships with a database called ...