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In the summer of 1980, Sams told Gates that Kildall wasn’t working out, and that the operating system issue was now Gates’ problem to solve. Gates picked up Kildall’s mess and rant with it. He gave Sams the promise that Kildall would not, he (Gates) would produce a detailed plan for an operating system by October. The only difference was that Gates promise without having an actual operating system to work with.
Throughout the 1980, Kildall’s failure to set a hard release date for CP/M-86 fueled a rising sense of panic among manufacturers who needed the operating system for their new 8086 machines. In effect, Kildall’s delays were holding the whole industry hostage.
Across town from Microsoft, a little computer maker called SCP (Seattle Computer Products), came up with a stopgap solution. A programmer there spent months working from the CP/M technical manual to write a new operating system so similar to CP/M that would allow all CP/M-compatible software to work on the new 8086 machines. He called the operating system QDOS (Quick and Dirty Operating System). SCP’s computers will use QDOS until CP/M-86 was released.
When gates and Allen heard about QDOS, they figured they might be able to meet IBM’s tight schedule by buying QDOS and then giving it a spit-shine and a new name. Allen knew the owner of SCP fairly well, and he negotiated the rights for Microsoft to use QDOS for the grand sum of $25,000.
The cash-starved owner at SCP took the money gladly, with no idea that IBM would be QDOS’s ultimate customer. It took several months of around-the-clock programming to massage, tweak, and test QDOS before Microsoft presented a finished product to IBM engineers under its new name: MS DOS (Microsoft Disk Operating System).