When you use a live video conversation in a chat session after you install Microsoft Windows XP Service Pack 2 (SP2), conversations may be broken, choppy, or jittery. Additionally, a Voice over IP (VoIP) connection may be choppy or break down completely. This behavior occurs only if the Quality of Service (QoS) Packet Scheduler is installed and active.
This problem may occur in any one of the following programs:
- Windows Messenger
- MSN Messenger
- AOL Instant Messenger
- Siemens optiClient (VoIP client)
This problem may occur when the following conditions are true:
- Your Internet connection is a Point-to-Point Protocol (PPP)-type connection, such as dial-up, Point-to-Point Protocol over Ethernet (PPPoE), or a digital subscriber line (DSL).
- The Quality of Service (QoS) service is enabled on your Internet connection. By default, the QoS service is enabled.
To work around this problem, disable the QoS Packet Scheduler. To do this, follow these steps:
- Click Start, and then click Control Panel.
- Click Network and Internet Connections.
- Click Network Connections.
- Right-click the icon for your network or your Internet connection, and then click Properties.
- In the This connection uses the following items list, click to clear the QoS Packet Scheduler check box.
- Click OK to close the network or Internet connection properties dialog box.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix. Note
If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note
The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
You must have Windows XP SP2 installed to install this hotfix.
For additional information about how to obtain the latest Windows XP service pack, click the following article number to view the article in the Microsoft Knowledge Base:
How to obtain the latest Windows XP service pack
You do not have to restart your computer after you apply this hotfix.
Hotfix replacement information
This hotfix is not replaced by any later hotfix.
You do not have to create or to modify any registry keys to use the hotfix that this package contains.
Hotfix file information
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone
tab in the Date and Time tool in Control Panel.
Date Time Version Size File name
04-Oct-2004 17:48 5.1.2600.2524 91,776 Ndiswan.sys
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
Description of the standard terminology that is used to describe Microsoft software updates
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.
More LifeCam video troubleshooting information is available in this Microsoft knowledge base article:933310
- Troubleshoot bad or no video or problems starting LifeCam software