KB21627 - "nc.windows.app.23790" error with Verizon AirCard

This article explains why a Verizon AirCard is disconnected from Network Connect every x minutes with the error message below:

nc.windows.app.23790

Network Connect seems to work just fine when a different Wi-Fi connection is used.

A user using a Verizon AirCard is disconnected from Network Connect every x minutes with the error message below:

nc.windows.app.23790

This happens because NDIS mode is enabled in Verizon Access Manager (as shown in the figure below). In certain cases, generic Novell device drivers that are present enable the NDIS mode to work.

The PCS VPN has this enabled.

 

Workaround

The workaround for this issue involves reducing the number of DHCP Inform packets sent out when the VPN connection is established.

This can be accomplished by:

• Disabling SLP DHCP discovery,
• Disabling DHCP used by the Novell Client, or
• Disabling the DHCP used by the ZENworks Agent to identify the nearest Middle Tier server.

Notes on the Workaround Options:

• The goal of these options is to reduce the number of DHCP Inform requests sent by Novell software to some number below the "forged" limit imposed by the AirCard Service Provider. On Verizon, this limit is 10 packets.
• These options are listed in no particular order. Different options or a combination of options may be appropriate for different environments.

Disable SLP DHCP discovery by disabling "Use DHCP for SLP" option

1. Right-click the red N icon in the system tray.
2. Click the Novell Client Properties menu option.
3. Click the Advanced Settings tab.
4. Select the Use DHCP for SLP option by clicking it.
5. Change the Setting to Off.
6. Click OK.

Note:

• For this workaround, the SLP configuration - SLP DA addresses and SLP Scope names must be hard-coded in the Novell Client configuration (they should not be solicited from DHCP). Changes to this hard-coded information can be deployed using the ZENworks application to update the related registry values.

Disable Novell client DHCP options by turning off all options on "DHCP Settings" tab in Novell Client Properties

1. Right-click the Red N icon in the system tray.
2. Click the Novell Client Properties menu option.
3. Click the DHCP Settings tab.
4. Clear all the check boxes.
5. Click OK.

Disable DHCP used by ZENworks agent to determine closest Middle Tier server by renaming NOVDHCP.DLL

1. Rename \system32\novell\novdhcp.dll to something else (for example, NOVDHCP.JRS).

If this change is made, the DLL cannot be found and used, thus disabling DHCP for the ZENworks agent.

Note:

• This workaround is available only if the ZENworks Agent is installed.