The president of Microsoft's Entertainment and Devices division, Robbie Bach, has announced he is to retire this autumn after 22 years with the company.
Bach will be best remembered as the business driving force behind the company's globally popular Xbox games console.
Bach's resignation comes shortly after chief technical officer J Allard quit the company, allegedly because of his disappointment over the decision to cancel his 'Courier' tablet computer project.
The announcement has prompted the company to take immediate steps to reform the management of the Entertainment and Devices division.
Microsoft CEO Steve Ballmer will take over as the boss of the division from 1 July until a suitable replacement can be found.
Ballmer taking over a division is nothing new - in the past, he has taken charge over departments he has felt dissatisfied with, including Windows business and Internet search.
Despite some reports suggesting Bach quit due to his dissatisfaction with Microsoft's mobile and game console strategies, Ballmer has insisted that Bach had been considering retirement for a long time, saying: "Robbie Bach's been thinking about the possibility of retiring and spending more time with his family. He and I talked about whether we should go ahead and announce that now or wait until after Christmas."