port problem

I am new at all this, but have spent a number of hours looking through the forum to see if there is an answer to my particular problem.
I haven't been able to find an answer, so here goes:

Arduino uno and vista

When I connect, the option under tools/serial port gives 2 options: com3 and com6. Com 3 is always ticked.
Checking on device manager, it shows the Arduino is set for com 6.
I have tried selecting both com3 and 6 in 4 different ports on my laptop but with no success.
What am I getting wrong?

Thanks in advance for any help.

did you install device drivers?

Yup, did that!

What is it that does not work for you - uploading a sketch? What error do you get ? (As in: what does "but with no success" mean?)

Its all a bit unpredictable really.

I have this evening uninstalled everything and then re installed the IDE and drivers.

When re installing, the software told me it was using com6. When I open a sketch and check the port there are 2 options, com3 and com6. I check com6, verify the sketch, upload and get the message no board at com6.

The sketch will not upload. On checking device manager, the arduino is on port 6. Interestingly, whichever usb port I use, device manager tells me its on com6.

Does this help?

This is not a programming question then at all - you are saying you can not access your Arduino at all. This is best done in the "Installation and Troubleshooting".

1: As said in one of the stickies : http://www.arduino.cc/en/Guide/Troubleshooting#upload has lots of information and suggestions for getting your Arduino software and hardware.

2: Do the loopback test as described in the loopback test entry

The IDE Help / Troubleshooting command takes you to lots of help about troubleshooting.

upload and get the message no board at com6.

Do you have the appropriate board selected?

Thanks for the help guys, I will work through the guidance suggested.

I have checked and yes I have the right board selected.

Updates later with luck