CDV: Seedy-Threepio's CD key verifier


Welcome to Seedy-Threepio's CD key verifier. This program checks if 10 digit Microsoft CD keys found in the wild are valid before you use them during the setup of a Microsoft software product. It does this by running some special algorithms on the data you enter into the program. Please note, at this time, CDV does not support Microsoft Office 97 keys, or OEM keys from PC manufacturers. These keys are validated in a slightly different way to standard 10 digit CD keys. Support for these keys may be implemented in the future.

What is a CD key?

In the early to mid 1990s, retail CDs for Microsoft software products, including Microsoft Office 95, Microsoft Plus! for Windows 95, Microsoft Plus! 98 and some versions of Flight Simulator, featured a special 10 digit code that users were required to enter during setup in order to verify that the copy of the software they were installing was, indeed, genuine and legally obtained. This code is known as a CD key. If you've lost your CD key for a piece of vintage Microsoft software, and you happen to find another key floating around on the internet, CDV will help you validate it before the setup program kicks you in the teeth.

CDV system requirements

CDV is a very small, light weight tool. Therefore, the system requirements for running CDV on your PC are extremely low.



An Intel/AMD x86-64 CPU is required. CDV is a 32-bit application, however, it will work on 64-bit systems as well. ARM CPUs are not supported.


8MB of system RAM. This is a recommended minimum.


A high quality sound card. CDV includes a special accessibility mode for blind/visually impaired users, for which a sound card is required.


Windows 9x

Windows NT

Downloading CDV

You can download the latest version of CDV by clicking here.

Installing CDV

When you download CDV and click on the Install_CDV executable file, you will be asked where you'd like to extract the program files. The CDV installer is a self-extracting archive, so files will be extracted automatically without the need for a file archival/compression utility. You can either manually specify a location to extract the files by typing a path into the text field, C:\CDV for instance, or you can click the browse button and choose a location via the resulting dialog. Note, for screen reader users, the browse button is unlabelled. However, it is the only unlabelled button in the dialog, so it should be easily identifiable.

Using CDV

To launch CDV, navigate to the folder where the CDV program files were placed during installation, and double click or press Enter on the cdv.exe file. Note that the filename will only show as "cdv" instead of "cdv.exe" if file extensions are hidden in Windows. If the resulting terminal window does not appear straight away, press Alt + Tab until you see it.

Accessibility notice for Windows 9x and NT 4.0 users

If you run CDV in Windows 9x or Windows NT 4.0, you will be presented with a special, self-voiced accessibility menu, where you'll have the option to use the program with speech and sound. Text is also shown on screen in this menu for those without a sound card. To run CDV with speech and sound, press the S key. Or, to run the program normally, without speech and sound, press the W key. CDV has these accessibility measures in place because in Windows 9x, MS-DOS is used for executing commands in a terminal, and no native screen reader support is included in MS-DOS. While there are screen readers available for DOS, they can be quite hard to both find and set up. Therefore, CDV includes self-voiced prompts that guide you through the various steps of using the program. Self-voiced means that speech is provided through prerecorded audio files, rather than relying on a screen reader or speech synthesizer. In Windows 2000 and higher, however, the accessibility menu will not be shown, and no self-voiced prompts will be given. The terminal in Windows 2000 and later versions of Windows is screen reader accessible out of the box, so such accessibility measures are not needed. Instead, you can simply press Enter to start using the program.

When you finally get into the program, there are 2 fields you must fill in. When you're finished entering data, press Enter to proceed to the next field.

The site number.

The first field you'll see is the site number field. The site number is the first 3 digits of the 10 digit CD key. Site numbers must meet the following criteria.

The key field

Next, you'll be asked to enter the last 7 digits of the CD key. This section has the following requirements.

Once all data has been entered, CDV will run the aforementioned mod 7 check on your key. If everything checks out, a success message will be shown, saying that the CD key is valid. The full 10 digit key will also be shown. If the check fails, however, CDV will simply tell you that your key is not valid. Finally, you'll be asked if you want to verify another CD key. Pressing Y at this prompt will allow you to enter another site number and 7 digit code, while pressing N will simply exit the program.