Thanks Driven, I wasn't sure if I could use those two (gain or lose) words with "market". What I am trying to say when I lose market is that people that before were purchasing my products now they are not. And gain will be the opposite.
Well, you would probably say, gain or lose sales then. If you say gain/lose market value, it means that you gain or lose popularity with the people who are buying your product which equates to sales. If you say gain/lose market share, it means that people who buy similar products to yours are buying more/less of your product than other brands. In your context, you cannot say gain/lose market.
If you say, "Microsoft gained a large market share quickly" it means that of all the computer companies, Microsoft got a large portion of the sales, quickly. (A large portion of sales in the same market as Microsoft.) Or you could say, "Microsoft increased sales quickly." You are correct in that you cannot say, "Microsoft gained market fast."