Up until the Surface line, Microsoft never shipped any computers at all, much less "malware ridden" ones. I think that exactly illuminates how high of a mountain Microsoft would have needed to climb to earn people's trust when Microsoft is also in general mainstream mindsets saddled with the problems of other company's behaviors.

But if the point was to save the marketshare of Windows phone products via retail store presence, Microsoft didn't have time, they were racing a losing money clock and the shareholders were watching retail operations worried Microsoft was just "throwing good money after bad".