How to retain previous code windows opening an existing visual studio 2010 solution?

When opening an existing solution in Visual Studio 2010 the code / classes previously working on开发者_StackOverflow中文版 no longer shows. Have to go to solution explorer and click each individual class again. This seemingly happened without making any changes to Visual Studio (odd.)

Is there an options setting that I am missing or any other solution to this event?

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Sounds like your solution options (.suo) file has become corrupt -- delete tht, and it should then persist open windows from the next time you close Visual Studio.