MIME is required to be set on the server to prevent visitors from being subject to unwanted symptoms that include crashing browsers.
The MIME types for Flash (.swf) and Splash (.spl) are as follows:
MIME Table Settings:
MIME Type: application/x-shockwave-flash Suffix: .swf
MIME Type: application/futuresplash Suffix: .spl
Each server software has its own method of mapping the cross reference of the MIME type to the file extension for that file.
Apache
Microsoft's Internet Information Server (IIS 1-3) (MM) 12048
MicroSoft Bulletin for IIS 1 through 3 (MS) Q142558
IIS version 4.0 Servers