Winmodem Device Does Not Work on Toshiba Portege 2000 After You Upgrade to Windows XP SP1

After you install Windows XP Service Pack 1 (SP1), the winmodem device no longer works on your Toshiba Portege 2000.

When you view the device in Device Manager, it is displayed with a yellow "!", which indicates that the device is experiencing problems.

The ALi chipset makes only one hardware ID available for the Audio Codec '97 (AC '97) controller. The available hardware ID is for audio. The audio driver also enumerates a child node for the modem. SP1 updates the audio node, which causes the issue for the winmodem device.

To resolve this issue, use one of the following methods. These methods are presented in order in which we recommend them.

Method 1: Use the Roll Back Driver Feature for the Audio Node

1. Right-click My Computer, and then click Properties.
2. Click the Hardware tab, and then click Device Manager.
3. Expand Modems, and then double-click the audio node for your modem.
4. Click the Driver tab, and then click Roll Back Driver.

Method 2: Edit the Ltsmwxp.inf File and Update the Driver

Edit the Ltsmwxp.inf file

1. Click Start, and then click Search.
2. Click All files and folders.
3. In the All or part of the file name box, type ltsmwxp.inf, and then click Search.
4. In the Search Results window, double-click Ltsmwxp.inf.
5. On the File Menu, click Save As, and save the file as Ltsmwxp.old.
6. Find the following line in the file:
   %ALI_AMR.Modem% = ALI_AMR.Modem, PCI\VEN_10B9&DEV_5450&SUBSYS_4C275349
7. After this line, add the following:%ALI_AMR.Modem% = ALI_AMR.Modem, {be20ddbf-3fb3-4add-a5c0-49be7ac20fb}\VEN_10B9&DEV_5450&SUBSYS_4C275349
   
   
8. On the File menu, click Save As, and save the file as Ltsmwxp.inf.
9. Note the location of this file, and then quit Notepad.

Update the Driver

1. Right-click My Computer, and then click Properties.
2. Click the Hardware tab, and then click Device Manager.
3. Expand Modems, and then double-click the audio node for your modem.
4. Click the Driver tab, and then click Update Driver.
5. In the Hardware Update Wizard, click Install from a list or specified location (Advanced), and then specify the location of the Ltsmwxp.inf file.
   
   NOTE: You may receive a message that says that the driver is unsigned.

Method 3: Edit the Registry

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

1. Click Start, and then click Run.
2. In the Open box, type regedit, and then click OK.
3. In Registry Editor, locate the following subkey:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Enum\{be20ddbf-3fb3-4add-a5c0-49be7ac20fb}\VEN_10B9&5450$SUBSYS_4C275349
4. To create a backup copy of the subkey, click the subkey, and then on the File menu, click Export.
5. Type a name for the backup copy in the File name box, click Selected branch, and then click Save.
   
   NOTE: If you need to restore this key after you complete this procedure, double-click this backup copy.
6. In the right pane, double-click the HardwareID key.
7. In the Value Data box, type the following:PCI\VEN_10B9&5450$SUBSYS_4C275349
   
   
8. Click OK, and then restart your computer.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.