Microsoft’s latest update of Office 2003 brought into question a series of security issues that blocked users from making use of certain file formats in Excel, PowerPoint, Word and CorelDraw. Following this unpleasant situation, Microsoft developers released a series of downloadable registry files that will undo the changes and fix the problem.

The Microsoft team blamed at first the insecure file formats, not only of other developers’ software, like CorelDraw, but their own: “Some older file formats, including some form Microsoft, are insecure. The decision to block the formats is strictly to protect your machine from being compromised,” said Viral Tarpara from Microsoft in a recent blog.

David LeBlanc, senior software development engineer for Microsoft Office said in his blog: “We stated that it was the file formats that were insecure, but it is actually not correct. A file format isn’t insecure – it’s the code that reads the formats that’s more or less secure. The parsers we use for these older formats aren’t as robust as the code we’ve written more recently, which is part of our decision to disable them by default.”

Considering the update not only affected Microsoft files, but also other developers’ too, LeBlanc added in his blog, but without mentioning any specific names: “Some of the file formats blocked are from products built by companies other than Microsoft, and we apologize for implying that there were any problems in those companies’ file formats.”

However, Microsoft was not the first to acknowledge the problem. Corel developers issued a public debate when they realized their .cdr file format was being blocked since the Office 2003 Service Pack 3 update. “We didn’t know where the issue was coming from,” said Gerard Metrallier, director of product management for Corel (Computerworld.com).

Consequently, Microsoft issued a public apology on Friday, by saying that they had made a mistake and made it hard for Office 2003 SP3 users to work around the registry issues. Accordingly, Microsoft developers added a series of downloadable files that will fix the problem automatically once installed.