Error Message: The Modem Is Not Installed or Configured for...

Applies to: Windows

If this article does not describe your hardware-related issue, please see the following Microsoft Web site to view more articles about hardware: IMPORTANT: This article contains information about editing the registry. Before you edit the registry, you should first make a backup copy of the registry files (System.dat and User.dat). Both are hidden files in the Windows folder.


When you try to create a new Dial-Up Networking connection, your modem may be missing from the Select A Device box. Also, if you try to use an existing Dial-Up Networking connection, you may receive the following error message:

Dial-Up Networking

Error 633: The modem is not installed or configured for Dial-Up Networking.
To check your modem configuration, double-click the Modems icon in Control Panel

Note that if you test your modem by clicking More Info on the Diagnostics tab in the Modems tool in Control Panel, your modem may respond normally and appear to be working correctly.


This issue can occur if either of the following conditions exists:

  • The Telephony Application Programming Interface (TAPI) service provider entry in the registry is missing or has been altered.
  • The Telephon.ini file is missing or damaged.


WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it.

To resolve this issue if the TAPI service provider entry in the registry is missing or has been altered, use Registry Editor to view the following registry key:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version\ Telephony\Providers

Modify the value of the ProviderFilename0 value to "TSP3216L.TSP" (without quotation marks), save these changes, quit Registry Editor, and then restart your computer.

To resolve this issue if the Telephon.ini file is missing or damaged, follow these steps:

  1. Click Start, point to Find, and then click Files Or Folders.
  2. In the Named box, type telephon.ini, and then click Find Now.
  3. If you do not find the Telephon.ini file, skip to step 4. If you do find the Telephon.ini file, right-click it, click Rename, type
    telephon.old, and then press ENTER.
  4. Quit the Find tool, click Start, click Run, type tapiini.exe, and then press ENTER.
  5. Restart your computer.