A co-author of this week's report that called Microsoft's operating systems dominance a "security-risk" has been fired.

Daniel Geer, who was chief technology officer of AtStake Inc. and who has nearly 30 years experience of technology and computer security, "learned Thursday he was no longer employed" by that firm, reports The Silicon Valley Mercury News.

The report warned that Microsoft's dominance of the global operating-systems market presents serious security risks, but blamed Microsoft's customers.

Willing to testify While the company claims the firing was in effect two days ago, and Microsoft denies involvement, the report says: "But critics said Geer's firing was reflective of Microsoft's far-reaching ability in Washington and across the technology industry to silence experts who complain about weaknesses in its software or its aggressive business practices. The Justice Department struggled years ago to find technology executives willing to testify against Microsoft in its antitrust trial."

One person familiar with Geer's situation said he was fired in a call Thursday morning. The report was announced in Washington the day before.

"AtStake has worked closely with Microsoft in the past, examining some of its software blueprints for security problems and providing consulting services", the report states.

The Mercury also reveals that a publishing company that creates products for chief security and chief information officers had refused to carry marketing information about the report, calling it "too sensitive" to send out.