Microsoft wields axe then twists knife

...that it was a bug in the software that led to the overpayment.

Here's the fun part...

In my experience, employees are asked to sign an agreement that they won't bad-mouth the employer, etc,etc in return for the severance check, which the employer is not obligated to provide, thus creating a contract.

If there is a contract, especially one that did not, in writing, specify the amount of the severance, good luck to Microsoft's legal beagles.

Here's the problem: Whatever Microsoft may have intended, there is the little problem that the employee signing on the dotted line acts in reliance on the severance check they receive. IE, I only did it because you were paying me a gazillion dollars. We had a deal.

Now -- the employee may not even have known the amount before signing, or it may simply be a matter of lotsa luck proving it, but...

As Nelson would say, "Ha ha!!".