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error - serial port COM4 already in use.

Discussion in 'Arduino' started by RMIM, Mar 16, 2013.

  1. RMIM

    RMIM Member

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    HI ALL,

    Bought my first Arduino. It worked perfectly out of the box for about 15mins then stopped and now I constantly get serial port COM4 already in use.

    I can't shake it. I spent many hours trying to fix it.

    However it does seem to work on my desktop windows 7.

    It refuses to work on my laptop windows 8 (but it did for a short while.)

    I found the following link

    http://arduino.cc/forum/index.php?topic=118321.0

    but did not help me.

    I upgraded to the new software Arduino 1.5.2, it did not help, I still get an error.

    Does anyone know a simple fix for this?

    Thanks
     
  2. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    Where did you install the arduino software?.... If you have installed into "Program files" you will struggle.... If you move the whole directory into "Your Documents" It should work correctly.... Administration rights are a bit of a pain with the arduino software.....
     
  3. RMIM

    RMIM Member

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    thanks for the reply Ian
    well I was hoping for a simple fix - fingers crossed.
     
  4. dave

    Dave New Member

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  5. RMIM

    RMIM Member

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    my god man, i need to buy you drink like your avatar. it worked. i searched for hours and never found that solution. thanks again.
     
  6. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    We had a young "work experience" lad in two months ago... He had a Windows 7 laptop. We installed the arduino software... When you select "Baud" ,"Com" etc... It cannot write the new settings to the config... So you only get it working once... After reboot... Again once.... I must admit it took me a while to sort it....
     
  7. RMIM

    RMIM Member

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    Perhaps that might fix my usb oscilloscope? I have a small usb oscilloscope that worked great in windows 7 but refuses in windows 8. Sadly the company that make it shut down before windows 8 came out I think, so I dont know if it's a driver problem or something similar to this.
     
  8. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    You can still run devices in comparability mode .. You need to try running as administrator first....
     
  9. RMIM

    RMIM Member

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    well I fought with it for a while then gave up. it needs java to work. it refused to even work on windows 7. Then I uninstalled the java update and it worked again.

    I will have to have another go of getting it work at some point. I do have a picoscope, but this one is a tiny usb stick type device. I liked it a lot.

    http://www.youtube.com/watch?v=j1DfiEW6RV8
     
  10. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    Uninstall it then re-install by using administration rights ( right click the install program and run as administrator)... Once installed run the application in the same fashion... You should only need to do it once..
     
  11. RMIM

    RMIM Member

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    Thanks for the reply Ian

    I found the problem. when installing the driver I got The hash for the file is not present in the specified catalog file. The file is likely corrupt or the victim of tampering.

    I was thinking I need a windows 8 driver. In fact I found a page with a driver. CP210x USB to UART Bridge VCP Drivers. http://www.silabs.com/products/mcu/Pages/USBtoUARTBridgeVCPDrivers.aspx

    But could not get it to install.

    Then I found a solution that disables Windows 8 checking of the driver's signature


    From the Metro Start Screen, open Settings (move your mouse to the bottom-right-corner of the screen and wait for the pop-out bar to appear, then click the Gear icon).
    Click ‘More PC Settings’.
    Click ‘General’.
    Scroll down, and click ‘Restart now’ under ‘Advanced startup’.
    Wait a bit.
    Click ‘Troubleshoot’.
    Click ‘Advanced Options’
    Click ‘Windows Startup Settings’
    Click Restart.
    When your computer restarts, select ‘Disable driver signature enforcement‘ from the list

    It now works! (The driver installs)

    Shame I could not get the windows 8 drive to work. Any clues?
     
    Last edited: Mar 18, 2013
  12. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    I have no experience with Windows 8 at this time.... I probably willl have to get used to it with my next laptop upgrade( due anytime now)

    Until then I can only assume that the admin rights are the same as 7..
     

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