Among the top executives that decided to leave Microsoft during this period of time one could find also veteran Pieter Knook, who will leave behind the world’s largest software maker for Vodafone. The mobile network operator announced on Thursday that Pieter Knook was going to work for the company as the director of its recently launched Internet Services unit.

So, after no less than 17 years with Microsoft, Pieter Knook seems to have decided it was time for him to move along and try something else. During the last five years, Knook was Microsoft’s senior vice president running its mobile business. But the die has bee cast and starting March 10, he will begin developing Vodafone’s mobile Internet strategy.

The mobile network operator has just launched the Internet Services unit, which is going to focus on provision of distinctive consumer web services.

Later on Thursday, Microsoft confirmed Pieter Knook’s departure and the Wall Street Journal reported that the software maker would name Andrew Lees to lead its mobile-communications business. Lees is currently a corporate vice president of Microsoft’s server and tools group.

Microsoft reportedly said that Knook “felt it was the right time to look at new opportunities.”

But it seems that Pieter Knook wasn’t the only one who felt this way, as Microsoft announced on Thursday that a few other top executives decided to leave the company. Steve Berkowitz, for example, was another key employee Microsoft lost just like that.