Unhandled Exception:
System.IO.IOException: Permission denied
  at System.IO.Ports.SerialPortStream.ThrowIOException () [0x00000] in <filename unknown>:0
  at System.IO.Ports.SerialPortStream..ctor (System.String portName, Int32 baudRate, Int32 dataBits, Parity parity, StopBits stopBits, Boolean dtrEnable, Boolean rtsEnable, Handshake handshake, Int32 readTimeout, Int32 writeTimeout, Int32 readBufferSize, Int32 writeBufferSize) [0x00000] in <filename unknown>:0
  at (wrapper remoting-invoke-with-check) System.IO.Ports.SerialPortStream:.ctor (string,int,int,System.IO.Ports.Parity,System.IO.Ports.StopBits,bool,bool,System.IO.Ports.Handshake,int,int,int,int)
  at System.IO.Ports.SerialPort.Open () [0x00000] in <filename unknown>:0
  at (wrapper remoting-invoke-with-check) System.IO.Ports.SerialPort:Open ()
  at teszt.MainClass.Main (System.String[] args) [0x00018] in /home/ubuntu/teszt/teszt/Program.cs:17
[ERROR] FATAL UNHANDLED EXCEPTION: System.IO.IOException: Permission denied
  at System.IO.Ports.SerialPortStream.ThrowIOException () [0x00000] in <filename unknown>:0
  at System.IO.Ports.SerialPortStream..ctor (System.String portName, Int32 baudRate, Int32 dataBits, Parity parity, StopBits stopBits, Boolean dtrEnable, Boolean rtsEnable, Handshake handshake, Int32 readTimeout, Int32 writeTimeout, Int32 readBufferSize, Int32 writeBufferSize) [0x00000] in <filename unknown>:0
  at (wrapper remoting-invoke-with-check) System.IO.Ports.SerialPortStream:.ctor (string,int,int,System.IO.Ports.Parity,System.IO.Ports.StopBits,bool,bool,System.IO.Ports.Handshake,int,int,int,int)
  at System.IO.Ports.SerialPort.Open () [0x00000] in <filename unknown>:0
  at (wrapper remoting-invoke-with-check) System.IO.Ports.SerialPort:Open ()
  at teszt.MainClass.Main (System.String[] args) [0x00018] in /home/ubuntu/teszt/teszt/Program.cs:17