Closing a maximized form

Thank you for your reply, yeah i written this close, but the action behind this code is first it will go to the normalized stage and den closing.You just tried to close a maximized form in a mdi , u can see this problem....

I have used this code....

foreach (Form f in Application.OpenForms)
{
     if(f.name!="frmabc")
     {
       f.close();
       break;
     }
}