>Is it legally OK to sell a commercial app using the suffix '.NET'?
>...

Hi Kevin,

That's an interesting question. I don't have an answer for you but I can tell you where to start looking - http://www.microsoft.com/permission/. If you find a definitive answer to this please post back here, I'm sure many would be interested in knowing.

My gut sense is that MS could not copyright or otherwise restrict anything as generic as '.net', but maybe '.NET' (upper case) is another story.

-Rick