Arduino to Max Serial port error

Hi,

I want to connect the serial data from my arduino IDE to Max but it seems to have a problem accessing my serial port while it's being used by the arduino.

If I open this patch first it can access the serial port fine, but my Arduino IDE can't connect to the serial port. And if I open the arduino IDE first and upload the code then I get this error in MAX:

"serial: error opening serial port"

Totally at a loss for why this is happening. See below the patch I'm using to get the serial data

Thanks.