Suzanne Ross is correct to say the new trains' operating system (Windows 95) was obsolete and riddled with bugs (Letters, August 13).

However, the reason the doors do not work correctly is because the trains have air conditioning.

As all IT users know, to solve a problem with Microsoft's operating system you need to close and re-open the windows.

On a serious note, as the application running the train systems must be bespoke and unique why isn't the underlying operating system Linux?

It runs faster and can do more on a smaller, cheaper computer than Windows so has a considerable price advantage over Seattle's offerings.

-David Room, Haywards Heath