Generally, Access denied to VNC Server error happens while trying to connect to a VNC server using a cloud connection.

Here at Ibmi Media, as part of our Server Management Services, we regularly help our Customers to resolve related VNC errors.

Nature of the error, Access denied to VNC Server 

While trying to connect to a VNC server using a cloud connection, we may receive the errors given below:

Access denied to VNC Server; please sign in to connect
Access is denied

Both the error messages deny access to VNC server and we will not be able to connect to VNC server.

Typically, errors look like below:

Error: Access denied to VNC Server; please sign in to connect

This message means that our VNC account has been signed out of VNC Viewer. This will happen if we have recently changed the password for our VNC account, for instance.

We can check why this has happened by clicking the red cross next to our name in the top right of VNC Viewer:

Error: Access is denied

How to fix the error, Access denied to VNC Server ?

1. Solution for Error: Access denied to VNC Server; please sign in to connect

To resolve the issue, click Sign in again and enter our RealVNC account credentials.

Once we see a green tick/check mark in the top right next to our name, try connecting to the VNC Server again.

2. Solution for Error: Access is denied

To allow other users and groups to connect, we will need to add the user or group to VNC Server's Users & Permissions.

We can either add a group of pre-registered users or individual accounts. Users can be registered from both local and domain accounts and groups.

When running VNC Server on Windows, users and groups can be selected using the Object Picker UI.

Once the user has been added, permissions can be set for that user/group and users should now be able to authenticate successfully.

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