Microsoft is planning to open up the .pst format, allowing third-party developers to create applications and services based on Outlook data. The development will give other software access to data such as email, calendar and contacts entries, potentially making it more accessible to mobile or cloud-computing services. Developers can currently access data stored in the .pst file, but only if Outlook is installed on the desktop client. Microsoft's proposals will allow that data to be accessed "on any platform and in any tool, without concerns about patents, and without the need to contact Microsoft in any way".
The company plans to release the technical documentation for the .pst file as part of the Open Specification Promise it announced back in 2008, although Microsoft hasn't said when the information will be released.
"This documentation is still in its early stages and work is ongoing," Paul Lorimer, group manager for Microsoft Office interoperability writes on the company's Interoperability blog.
"We are 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."
The move could be good news for Microsoft's rivals, making it easier to port data from Outlook to cloud-computing services such as Google Apps. Last month Google announced its own 'Data Liberation Front', a group of the company's engineers who are dedicated to freeing data from Google services such as Gmail, Docs and and Blogger.
From Microsoft's point of view, the initiative could cement .pst's position as the data format of choice for email/calendaring applications
