When you want to serve up a new type of file that Microsoft’s Internet Information Server (IIS) does not recognize, you need to add a MIME type. With older versions of IIS this was done manually using the Registry Editor. Fortunately it is a lot easier with IIS version 4. First, run Microsoft Internet Service Manager from the Programs folder on the Start menu. Right-click on the server name, and then select Properties from the pop up menu. On the Internet Information Server tab, click on the File Types button. In the File Types dialog box, select the New Type button. In the Associated Extension box, type in the filename extension of the new file type being added. For instance, Macromedia’s Shockwave extension is .swf. In the Content Type (MIME) box, type the MIME description, which consists of two parts separated by a slash. For instance, Shockwave’s description is “application/x-shockwave-flash” without the quotes. Click OK to exit the Properties dialog box and exit Microsoft Internet Service Manager.