The man who runs Munich's central IT says there is no practical reason for the city to write off millions of euros and years of work to ditch its Linux-based OS for Windows.The city authority is widely expected to swap Linux for Windows, due to support among Munich's ruling SPD-CSU coalition for phasing out the use of open-source software.Last month, the general council backed a proposal that the administration should investigate how long it will take and how much it will cost to build a Windows 10 client. Once the details are known, the council will vote on whether Windows should replace LiMux, a custom version of the Ubuntu OS that is used by more than 15,000 staff across the authority. The changeover would take place by 2021.