FileZilla Client Tutorial (en)

Aluminum window have a dearcotive trim that actually hold the glass in place like putty used to of old wood windows. you will need to use a thin blade perhaps a sturdy razor knife to gently get between the trim base of the window frame. Lift gently so you can get under it with the putty knife and work toward the corners and it should pop up. Replace your window applyong a thin bead of silicon first to secure the window and seal from heat/cold loss then snap the trim back in place. Not difficult at all.