Move the file to your C:\Program Files\QuickTime\QTSystem folder.
Useful for users of QuickTime for Windows 7.5.0 only (this is where Apple removed Indeo 4). In QuickTime 7.5.5 Apple removed all versions of Indeo, and seems to have hard-coded this into the player, as no added plug-in will restore playback.
Download Indeo4.qtx (Windows (all))
File size: 747,008 bytes
Indeo Video 4 Plugin for QuickTime for Windows was added to MovieCodec.com in Movie Codec (07-30-2008).