the playback of Indeo encoded video: regsvr32 ir50_32.dll Security advisory The Microsoft Windows implementation of the Indeo codec contains several security vulnerabilities and one should not play Indeo videos from untrusted sources. Microsoft tried to remove them in XP SP1 but had to release a hotfix to add it back. The codec was originally licensed from Intel and Microsoft likely do not have the source code that would be required to fix the vulnerabilities. On fully patched systems and all Windows Vista and later systems, the Indeo codec is partially disabled in most circumstances. References External links Ligos Indeo Codecs – Ligos Corporation (archived) Indeo Support (archived) Literature Intel software Video codecs