Error message: "A connection to the remote computer could not be established

03/26/2020 258 41116

DESCRIPTION:

When connecting to an appliance using a SSLVPN tunnel, such as NetExtender, Connect Tunnel, On Demand Tunnel, a user gets the following error from the client:

A connection to the remote computer could not be established. You might need to change the network settings for this connection.

The user is able to browse realms on the appliance, but cannot establish a tunnel to it.  In ngutil output, the user sees the following error:

Error 0x000002D0: A connection to the remote computer could not be established. You might need to change the network settings for this connection. For further assistance, click more Info or search help and support center for this error number.

RESOLUTION:

The tunnel clients use RAS to bring up a virtual adapter.  Error 0x000002D0 is a Microsoft RAS (Remote Access Services) error; the error number corresponds to RAS error 720 (2D0 is 720 in hexadecimal).  Microsoft has more information regarding error 720 in this KB article.

The ultimate cause of this issue has not been determined, but SonicWall support has determined that the issue seems to occur when the WAN miniport (IP and PPTP) network devices are deleted, corrupted, or otherwise broken.  In one particular case, a notebook (a Lenovo ThinkPad with ThinkVantage software) exhibited this behavior and the issue had to be resolved by reinstalling the WAN miniport (IP) device shown on this page.  In another instance the resolution was to remove both the WAN miniport (IP) and WAN miniport (PPTP) devices in order to resolve this issue.