Cisco Unity

Cisco Unity ViewMail for Outlook (VMO): Silence During Playback Over the Phone

Document ID: 4317

Updated: Feb 02, 2006



ViewMail for Outlook uses Distributed Component Object Model (DCOM) to communicate with the Cisco Unity server and in some scenarios, a DCOM call to the server will fail. No audio is heard when Cisco Unity plays voice mail over the phone by using ViewMail. This symptom has only been reported on Windows 95/98.

This document describes the workarounds to correct this problem.

Before You Begin


Refer to Cisco Technical Tips Conventions for more information on document conventions.


There are no specific prerequisites for this document.

Components Used

The information in this document is based on all versions of Cisco Unity for Exchange.

The information presented in this document was created from devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If you are working in a live network, ensure that you understand the potential impact of any command before using it.


No audio is heard when Cisco Unity plays voice mail over the phone by using ViewMail. This symptom has only been reported on Windows 95/98.


The solutions to this problem are explained in detail below. While we do not know the root cause of this problem, the following two workarounds will correct the problem.

Install Latest Version of ViewMail for Outlook

Install the latest version of ViewMail for Outlook. It is included with the CD image of the latest version of Cisco Unity, which you can download from CCO.

Share Access Control

From the Windows 95/98 desktop, perform the following steps.

  1. Right-click the Network Neighborhood icon.

  2. Click Properties > Access Control.

  3. Choose Share-Level Access Control.

VMO can be updated independent of the Cisco Unity version. It is recommended to have the latest VMO version installed. See the Cisco Unity Release Notes for information on compatible Unity and VMO versions.

Upgrade the Microsoft Exchange System Manager

The silence of voice messages through the VMO during playback can also occur if the the Microsoft Exchange server has upgraded or moved to a different partner exchange server. If the partner server is upgraded, make sure that the Microsoft Exchange System Manager on the Cisco Unity server is also upgraded. Then, rerun the Message Store Configuration Wizard (MSCW) and point it to the new/upgraded partner exchange server.

Note: The Microsoft Exchange System Manager provides the Messaging Application Programming Interface (MAPI) subsystem that Cisco Unity requires in order to communicate with Microsoft Exchange.

Problem: Delay while Accessing the Voicemail

When you use VMO to play voicemail on the IP phones, the voicemail takes at least 5 to 50 seconds to start playing.


In order to resolve this issue, verify these items:

  • The HOSTS and LMHOSTS files are properly updated in the cluster, or you can have a DNS server configured with the host name and IP address of the server so that the server name is resolved properly. Refer to Basic DNS Troubleshooting for Cisco Unity Servers for more information.

  • There is no NIC teaming enabled on Unity server.

Related Information

Updated: Feb 02, 2006
Document ID: 4317