This is a new ergonomic feature in Windows. Windows checks if you are using a touch screen, the menu will open on the left side, the reason is that the human hand cover is on the right side of the zone pressed / pressed (the mouse pointer does not do this).
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I found my essence for myself :-) you need to select Tablet PC settings Left hand drive , this will solve your problem.
This will launch the tablet settings dialog (even if you donβt have a tablet).
Select the "Other" tab.
In the "Handedness" section, select the checkbox in the left hand.
Click OK.
Look at this information from Microsoft: http://answers.microsoft.com/en-us/windows/forum/windows_7-desktop/windows-7-application-menus-drop-to-left-instead/2d362701-90e4-4ea6 -a3a1-c1391a3d2bea
Do not forget to mark the answer.
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