First off, let me make this clear; There is no such thing as free. Now I've made that clear, there is no reputable company that will provide a customer with a free solution such as a VPS, especially if (and I'm just guessing here) you're looking for one that utilizes an operating system such as Windows. The provider not only pays for the space that you are renting out, but they also pay for the operating system license which even under an SPLA agreement (My company is a Microsft Partner with an SPLA Agreement) can be quite pricey. There are a lot of risks that business owners take by offering hosting solutions, such as renting space to spammers. If any provider were to offer a free solution, they would risk being flooded with new orders only to have their IP space blacklisted. I recommend spending the $20-30 bucks to get yourself a Windows VPS if that is what you are looking for.