avrdude: ser_open(): can't set com-state for "\\.\COM9" ERROR when uploading

Hi
Im getting an error:avrdude: ser_open(): can't set com-state for "\.\COM9" when i try to upload anything to my ardunio mega 2560

Also there is a green Led that is constantly blinking. Can anyone provide some help. Thanks

Error message paste:
Arduino: 1.6.5 (Windows 8.1), Board: "Arduino Mega or Mega 2560, ATmega2560 (Mega 2560)"

Sketch uses 49,222 bytes (19%) of program storage space. Maximum is 253,952 bytes.

Global variables use 3,518 bytes (42%) of dynamic memory, leaving 4,674 bytes for local variables. Maximum is 8,192 bytes.

avrdude: ser_open(): can't set com-state for "\.\COM9"

avrdude: ser_drain(): read error: The handle is invalid.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
"Show verbose output during compilation"
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