Microsoft employees Instagram/Microsoft Life Microsoft employees knew that a layoff was coming, and soon, but they were not fully prepared for this one, a Microsoft employee tells Business Insider.

"The feeling inside Microsoft on main campus is a bit shell-shocked at the size of the planned cuts," this person, a longtime Microsoft employee who was not let go today, told us.

The company plans to cut 18,000 total over six months with 13,000 let go today and 12,500 cut from Nokia, it said today.

Because Satya Nadella is known within the company for cutting middle management, and because the feeling among Microsoft employees is that there was plenty of fat to cut, middle managers were the most worried, the source says.

People in Microsoft (particularly middle managers) were also alerting other employees that something was going on through LinkedIn alerts. All of a sudden, a lot of Microsoft employees started updating their LinkedIn profiles and photos.

Although most of the Microsoft employees being let go should have found out today, Nadella has also put everyone on notice for the next six months. There's still 5,000 cuts left to make, and that's stressing people out, the source says.

"The next six months will be a drain on morale," our source says. "Cut now! Get the surgery over with and move on."

Then again, Microsoft also has about 3,200 job openings, according to Glassdoor.com. So perhaps some portion of those people will transfer to a new team in the next six months, instead of leaving the company altogether.