Back in February, Microsoft released
public specifications for PST files, the databases used by Outlook for storing and archiving e-mail. To these specifications, Microsoft has now added a pair of developer-oriented open source projects
: the PST Data Structure View Tool
for cracking open PSTs to browse inside them, and the PST File Format SDK
, a cross-platform C++ library for working with PST files programmatically.
The SDK project is not yet finished; presently it only provides read-only access to PST data, though write support is planned. Both tools are released using under the Apache License 2.0. This means that they can be incorporated into proprietary, closed-source projects, as well as other open source projects.