Microsoft is once again inviting members of the hacking community into its Redmond, Washington, campus to show the software giant where it's gone wrong.

The company's latest Blue Hat conference kicked off Wednesday with talks on mobile security, hardware hacking, Microsoft's security tools and the underground vulnerability economy.

Microsoft began hosting these events two years ago as a way to foster dialogue between the company's security team and external security researchers, many of whom have been critical of the company's approach to security.

Typically held twice a year, the Blue Hat conferences are closed to most outsiders but draw hundreds of Microsoft employees.

The name Blue Hat derives from the Black Hat security conferences. The "Blue" part comes from the color of badges that Microsoft staffers wear on campus.

The conference gives the security community a chance to share information with Microsoft, said Robert Hansen, CEO of Web security consultancy Sectheory.com, who will be talking about Web hacking at the conference. "We're all just starting to build relationships with each other," he said.

Other speakers at this week's show include David Maynor and Robert Graham of Errata Security; Kevin Mahaffey and John Hering of Flexilis, and Rob Thomas of Team Cymru.

On Wednesday Blue Hat speakers are giving 30 minute executive-level presentations. More in-depth technical talks are planned for Thursday.