I open SSMS 2012 from the standard installed link. Open query window. Next I double click on the .sqlplan file and the next instance of SSMS 2012 is opened. When I close second instance the SqlStudio.bin file is overwritten with default settings (not mine). When I close the first instance the settings are overwritten again with proper values. The problem comes when I close the first instance and then the second one. In this case I lose my settings. The problem does not occur if on the second instance I open additional query tab.