Keep Getting avrdude error message after uploading?

Hey guys...I keep getting the following error when i try to upload an example of an LCD sketch...

avrdude: Version 6.0.1, compiled on Apr 3 2014 at 23:12:16 Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/ Copyright (c) 2007-2009 Joerg Wunsch

System wide configuration file is "C:\Program Files (x86)\Arduino/hardware/tools/avr/etc/avrdude.conf"

Using Port : COM6 Using Programmer : wiring Overriding Baud Rate : 115200 avrdude: ser_open(): can't open device "\.\COM6": The system cannot find the file specified.

avrdude: wiring_open(): releasing DTR/RTS avrdude: wiring_open(): asserting DTR/RTS avrdude: ser_drain(): read error: The handle is invalid.

Any ideas what could cause this? I recently just installed an updated version of the IDE (1.5) in a different spot on the same computer over an older version (1.0). Do you guys think there conflicts with the drivers for the arduino? I can't figure it out....

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Actually, I think I fixed it by pressing the reset button. Thanks anyways :)

Also, not sure if the amount of power going to the arduino had something to do with it. When I added a 9v DC power supply to the board, the error goes away, so the screen may have been sucking down too much power.