SAN FRANCISCO--Microsoft's operating systems are still vulnerable to attacks, but more often than not it's older versions that are taking the big hits.

That was the message from Scott Charney, corporate vice president in Microsoft's Trustworthy Computing group, when he sat down with me on Tuesday. We chatted about the latest threats, including Conficker. The much-maligned Windows Vista, he noted, wasn't hit in the way that older versions of the operating system were.

"Some of those widespread exploits take advantage of older platforms," Charney said in an interview, following his keynote speech at the RSA 2009 conference here.

With Windows 7, Microsoft is trying to take security into a few more areas, such as extending encryption to removable devices.

Charney also noted that, as a whole, the Internet still should be safer than it is.

"There is still a sense that it is not safe enough," Charney said. "It was not built for the uses that we currently use it for, all these commercial transactions."

One of the answers, he said, is adding more security features into the PC hardware.

"In a nutshell, software is malleable and hardware is harder to tamper with," he said.

For my complete interview with Charney, check out the video below: