Microsoft has launched a public beta of the much-awaited Power Pack 1 for its Windows Home Server product that, in addition to bring several enhancements and patches for the operating system, will finally fix a long-standing data corruption bug that could result in lost files in units with two or more hard drives.

Power Pack 1 was originally announced five months ago at CES, but its public debut was pushed back to await the fix for the data corruption bug – which turned out to be a complex one as it was buried deep at an extremely low level of the operating system, the Drive Extender feature. Besides fixing the data corruption bug, it also adds quite a bit of new functionality including support for PCs running Windows Vista x64 editions, easier and enhanced remote access capabilities, better energy efficiency, and more.

Microsoft says it is working closely with the WHS community to gather feedback before releasing the final product, but you can already get the beta update package for your existing Windows Home Server system at Microsoft Connect. Of course if you’re going to apply the update to a live system, be sure to back everything up first.