Getting Error "Serial port 'COM38' already in use. Try quiting..."

hey

im newbie field, got self multiwii se 2.5 ftdi begin. when try upload code arduino ide i'm getting error "serial port 'com38' in use. try quitting programs may using it."

i have been trying solve error on 2 days now. please me : /

other info: running windows 8
using arduino-1.0.5-r2-windows
trying upload multiwii_2_3

please

Arduino Forum > Using Arduino > Installation & Troubleshooting > Getting Error "Serial port 'COM38' already in use. Try quiting..."

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