Error connecting to second arduino uno

Development Tools IDE 1.x
1

I got a second Arduino uno and I am trying to use it on my same laptop (wondows 8.1) as I have been using a different Arduino uno for a month. I can’t get the second Arduino to work, I think maybe because my laptop had already connected to a first (monogamous relationship?)

When I plug in the second Arduino:
the green power light is on, and,
pin 13 is repeatedly blinking pretty fast (about 4 times a second)

When I open the IDE under tools:
Board is “Arduino Uno”
“Port” is greyed out and cannot select anything.

In the device manager under ports and com:
shows “Arduino uno on com 4” (maybe first Arduino?)

When I try to download a sketch, I get the error:
can’t open device “\.\COM4”: The system cannot find the file specified.

When I connect my original arduino uno again, it works just fine. Can upload sketches no problem.

Is there any special procedure for using a second Arduino uno with the same laptop? Do I have to install the drivers again? Do I have to force some firmware install that was done automatically the first time?

Can I keep using two Arduino unos with the same laptop? Or will loading drivers for the second mean I can’t connect to the first anymore?

Thanks
Drew

2

drew345:
Is there any special procedure for using a second Arduino uno with the same laptop? Do I have to install the drivers again? Do I have to force some firmware install that was done automatically the first time?

If the "UNO" is a third-party copy you may need to install drivers for the USB-to-Serial chip used on many inexpensive clones. Look at the chip near the USB connector to figure out what chip you need drivers for.

3

Thank you very much. I am trying to track down the drivers. It is an Arduino provided by the competition committee so it is not clear who it was purchased from. Thanks for the tip about looking at the chip near the USB connector.