Sketch uses 444 bytes (1%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can't open device "\.\COM3": Access is denied.
An error occurred while uploading the sketch
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Arduino: 1.8.5 (Windows 7), Board: "Arduino/Genuino Uno"
Archiving built core (caching) in: C:\Users\Louis\AppData\Local\Temp\arduino_cache_450120\core\core_arduino_avr_uno_0c812875ac70eb4a9b385d8fb077f54c.a
Sketch uses 444 bytes (1%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude -CC:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf -v -patmega328p -carduino -PCOM3 -b115200 -D -Uflash:w:C:\Users\Louis\AppData\Local\Temp\arduino_build_935021/sketch_dec01a.ino.hex:i
avrdude: Version 6.3, compiled on Jan 17 2017 at 12:00:53
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"
Using Port : COM3
Using Programmer : arduino
Overriding Baud Rate : 115200
An error occurred while uploading the sketch
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Hmmm, that's only slightly more informative. Usually I would expect AVRDUDE to give more information on the cause of the failure. It's strange that you originally got the "avrdude: ser_open(): can't open device "\\.\COM3": Access is denied." but no longer. That error indicates that another program has the port open, though sometimes it could happen if the port was locked open by a previous upload that went wrong.
Are you sure the Uno is on COM3? Does it show up under the Tools > Port menu? If you unplug the Uno from your computer, wait a little while, and then open the Tools > Port menu again the Uno's COM port should disappear, and vice versa with plugging it in.
Arduino: 1.8.5 (Windows 7), Board: "Arduino/Genuino Uno"
Archiving built core (caching) in: C:\Users\Louis\AppData\Local\Temp\arduino_cache_7568\core\core_arduino_avr_uno_0c812875ac70eb4a9b385d8fb077f54c.a
Sketch uses 444 bytes (1%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude -CC:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf -v -patmega328p -carduino -PCOM3 -b115200 -D -Uflash:w:C:\Users\Louis\AppData\Local\Temp\arduino_build_655711/sketch_dec01a.ino.hex:i
avrdude: Version 6.3, compiled on Jan 17 2017 at 12:00:53
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"
Using Port : COM3
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: ser_open(): can't open device "\\.\COM3": The system cannot find the file specified.
avrdude done. Thank you.
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
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pert:
Are you sure the Uno is on COM3? Does it show up under the Tools > Port menu? If you unplug the Uno from your computer, wait a little while, and then open the Tools > Port menu again the Uno's COM port should disappear, and vice versa with plugging it in.
Arduino: 1.8.5 (Windows 7), Board: "Arduino/Genuino Uno"
Sketch uses 2672 bytes (8%) of program storage space. Maximum is 32256 bytes.
Global variables use 250 bytes (12%) of dynamic memory, leaving 1798 bytes for local variables. Maximum is 2048 bytes.
An error occurred while uploading the sketch
avrdude: ser_open(): can't open device "\\.\COM3": The system cannot find the file specified.
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
Exception in thread "Thread-56" java.util.ConcurrentModificationException
at java.util.LinkedList$LLSpliterator.forEachRemaining(LinkedList.java:1239)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151)
at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418)
at cc.arduino.contributions.libraries.LibrariesIndexer.rescanLibraries(LibrariesIndexer.java:127)
at cc.arduino.contributions.libraries.LibrariesIndexer.setLibrariesFolders(LibrariesIndexer.java:106)
at processing.app.BaseNoGui.onBoardOrPortChange(BaseNoGui.java:682)
at processing.app.Base.onBoardOrPortChange(Base.java:1313)
at processing.app.Editor$DefaultExportHandler.run(Editor.java:2198)
at java.lang.Thread.run(Thread.java:748)
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