Microsoft today announced that it will be releasing documentation for the .PST file format, which is used for storing data ranging from e-mail to calendar to contacts in Outlook Personal Folders, but did not provide a deadline for itself. Microsoft is currently engaging directly with industry experts and interested customers to gather feedback on the quality of the technical documentation to ensure that it is clear and useful.

When it is complete, the documentation will be released under in the company's Open Specification Promise (OPS), a program under which Microsoft promises not to sue developers who use specifications included in the program. The technical documentation will detail how the data is stored, will include guidance for accessing that data from other software applications, will highlight the structure of the .PST file, will show details like how to navigate the folder hierarchy, and explain how to access the individual data objects and properties.

Developers will thus be able to read, create, and interoperate with the data in .PST files in server and client scenarios without concerns about patents, and without the need to contact Microsoft. Anyone will be able to implement the .PST file format on any platform and in any tool, using the programming language and platform of their choice.

The company says that providing access to the documentation will facilitate interoperability by enabling customers and vendors to access their data in .PST files across a variety of platforms. Organizations that need to exchange key corporate data in and out of Outlook, upload to the cloud, or comply with corporate governance policies, will find this particularly useful.

On the one hand, this could improve Microsoft's chances to make the .PST file format the unofficial standard in the area of e-mail data storage, while it's equally possible that it could help Outlook and Exchange competitors make it easier for companies to switch away from Redmond's products. Microsoft wants its message to be that this is a good move, as it will make the data more portable across various applications and platforms.