PySerial could not open port COM4: [Error 5] Access is denied - please help

[Temia Eszteri]

On Wed, 27 Jun 2012 22:18:59 +0000 (UTC), Grant Edwards
<invalid at invalid.invalid> wrote:

>> Can you post a small example showing what you're doing?
>
>The best way to get help is to write as small a program as possible
>that demonstrates the problem, and post it.  I'll help you get
>started...
>
>Does this program work?
>
>    import serial
>    ser = serial.Serial("COM4")
>    ser.close()
>
>At the moment, I don't have access to a Windows machine, but I think
>the above should run without any errors.  If it works, then you've
>successfully opened and closed the COM4 port.  Start adding
>"features", in increments as small as possible, until the program
>fails.
>
>Then try to remove stuff that's not needed while still keeping the
>failure.
>
>IOW, try to find the smallest possible program that fails.
>
>Usually, in the process of doing that, you'll figure out what you were
>doing wrong.  If not, post the smallest failing program you can come
>up with, and somebody will be able to help.
>
>If you won't show us what you're doing, we can't tell you what you're
>doing wrong.

Actually, I believe someone in an earlier thread in the newsgroup or
elsewhere pointed out that serial ports automatically open under
Windows. I'd have to look it back up when I have the time, which I
don't have at the moment, unfortunately.

~Temia
-- 
The amazing programming device: fuelled entirely by coffee, it codes while
awake and tests while asleep!