Windows 7, Arduino Uno: Can not Compile (upoload)

Ho there,

I have seen that the following mistake appeared already several times, but i could not find any method solving this problem for my case, i hope somebody has an idea anyway.

Iam using Windows 7 and Arduino 1.0.5-r2 for an arduino UNO board.

In around 19 of 20 times when i try to compile or upload any sketch i recieve the following error (see fat message below):

C:\arduino-1.0.5-r2-windows\arduino-1.0.5-r2\hardware\tools\avr\bin\avr-ar rcs C:\Users\Tom\AppData\Local\Temp\build5419200730988205964.tmp\core.a C:\Users\Tom\AppData\Local\Temp\build5419200730988205964.tmp\IPAddress.cpp.o

C:\arduino-1.0.5-r2-windows\arduino-1.0.5-r2\hardware\tools\avr\bin\avr-ar rcs C:\Users\Tom\AppData\Local\Temp\build5419200730988205964.tmp\core.a C:\Users\Tom\AppData\Local\Temp\build5419200730988205964.tmp\main.cpp.o

C:\arduino-1.0.5-r2-windows\arduino-1.0.5-r2\hardware\tools\avr\bin\avr-ar rcs C:\Users\Tom\AppData\Local\Temp\build5419200730988205964.tmp\core.a C:\Users\Tom\AppData\Local\Temp\build5419200730988205964.tmp\new.cpp.o

C:\arduino-1.0.5-r2-windows\arduino-1.0.5-r2\hardware\tools\avr\bin\avr-ar: unable to rename 'core.a'; reason: File exists

I tried now since one day several things, in deatail: installed several versions, checked permission rights, installed in different directories, deleted temp folders before using, ..... nothing worked.

Do you have any ideas? (I want to emphasize that it works extremely seldom, all in all 2 times during 1 day of trying, yes thats really deeply frustrating =( )

Perhaps you have some old files mixed with some new Arduino files.
Keep your folder with your project folders, try to remove everything else from the Arduino.
Try also to remove everything of Java.

Download the Arduino IDE, and unpack in a folder. Run it from that folder. Set your project folder in the settings, and give it a try.
You could also try the Arduino IDE 1.5.7 BETA. Unpack it in a new folder, set your projects folder and you can give that a try, and the other version still can be used.

If the problem suddenly appears again, do a harddisk check.

With the new version 1.5.7 'Beta it works. Thank you very, very very much mate. Of course i dont know if it is a little early as i just tried to compile and upload once. But both trys worked. Good Job! :*