Driver Details

Conexant D400 External USB 56K Modem Diagnostics Utility

This package provides the Conexant D400 External USB 56K Modem Diagnostics Utility and is supported on Inspiron, OptiPlex, Vostro Notebook and Latitude models that are running the following Windows Operating Systems: XP, Vista (64-bit) and Windows 7 (64-bit).

Fixes & Enhancements

- Fixed Displayed Icon in Control Panel Window.
- Fixed Program Compatibility Assistant message asking "Did this control panel work correctly?" about Modem Diagnostic DLL pops-up on Vista 64-bit OS when diagnostic tool is opened and closed after the installation.
- Removed all references of the files of dmdm32.cpl and dmdm64.cpl.

- Not Applicable


Version MdmDiag64_1.0.28.0, A01



Release date

02 Aug 2013

Last Updated

21 Mar 2014



Available formats

File Format:Hard-Drive
Download Type:HTTP
File Size: 1MB
Format DescriptionThis file contains a compressed (or zipped) set of files. Download the file to a folder on your hard drive, and then run (double-click) it to unzip the set of files. Follow the instructions to complete the installation.
To ensure the integrity of your download, please verify the checksum value.

By downloading, you accept the terms of the Dell Software License Agreement.

Supported Operating Systems

Windows 7, 64-bit
Windows Vista, 64-bit
Windows XP, 64-bit

Applies to

Conexant D400 External USB 56K Modem

Installation instructions

Hard Drive Installation (via WinZip) with Setup.exe File


1.Click Download File, to download the file.
2. When the File Download window appears, click Save or Save this program to disk and click OK. The Save In: window appears.
3. From the Save In: field, click the down arrow then click to select Desktop and click Save. The file will download to your desktop.
4. If the Download Complete window appears, click Close. The file icon appears on your desktop.


1.Double-click the new icon on the desktop
2.The Self-Extracting window appears and prompts you to extract or unzip to "C:\DELL\DRIVERS\2M98F". (Where '2M98F' is the name of the file to be downloaded). Write down this path so the executable (I.e.Setup.exe) file can be found later.
3. The Self-Extractor window appears.
4. Click OK.
5. After completing the file extraction, if the Self-Extractor window is still open, close it.
6. Click Start button and then click Run.
7. Type "C:\DELL\DRIVERS\2M98F" (where '2M98F' isthe name of the file) in the Open textbox and then click OK.
8. Follow the on-screen installation instructions.
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Drivers help and tutorials

Warning: Do not turn off your computer or disconnect from your power source while updating the BIOS/Firmware or you may harm your computer. During the update, your computer will restart and you will briefly see a black screen.

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This driver has been tested by both the independent software vendor (ISV) and Dell on the operating systems, graphics cards, and application supported by your device to ensure maximum compatibility and performance. Details
Dell recommends applying this update during your next scheduled update cycle. The update contains feature enhancements or changes that will help keep your system software current and compatible with other system modules (firmware, BIOS, drivers and software).