Earlier this month, Microsoft announced that several file formats in Office 2003 were going to be blocked when people installed the latest service pack, because Microsoft felt the formats has security problems. Evidently enough people complained that the company retracted its actions AND said the formats weren't to blame, but that the "the parsing code that Office 2003 uses to open and save the file types that is less secure."
Microsoft's actions are a great example of one of the problems we can have in ensuring that files remain accessible for the long term. A company may decide not to recognize older formats, thus making those formats unavailable for use. Unfortunately, companies have the right to make these type of decisions about their proprietary formats.
Technorati tag: Digital Preservation