the computer stoped detecting the arduino

I work with the uno3 for some time, had no problems so far.

I tried to set up a servo motor with the knop example from this site, at first it worked great.
after a minute of playing with it, everything stoped working and now I cant see the arduino in the opening tab, just COM3.
when I'm connecting the arduino to my computer the board lights up, and the 5v output works.
but the there is no sound from the computer telling me something has been connected and there is no smell of something that burned...

thanks
golan

Did you disconnect everything from the board before trying to reconnect to the computer ?

Also what OS ?
Which IDE ?
Which boards version (in the IDE) ?
Do the leds on the board light up and how do they blink etc. ?

IDE 1.6.7
windows 10-64 bit
I connected the LED from the 5v to ground just to see if it works and it does.
I'm not sure what you mean by the board version, where can i check it?

Board version can be found if you go to.

TOOLS
BOARD
BOARD MANAGER

the current version for "Arduino AVR Boards" is 1.6.12 here but it may even show 1.6.13 as I keep getting offered an upgrade but it doesn't show any that need it.

I will presume you used a resistor with the LED and didn't just plug it in.

In device manager what do you see for com devices ?
Should be listed as an Arduino or maybe even CH340 on whatever COM
If you don't see anything other than that then there is a chance its a driver issue as WIN 10 did some updates a short while ago that broke a lot of USB devices (especially web cams) requiring driver re-installs in most cases.

Could you by any chance post a pic of both sides of the board (decent quality ones)
Also if you have any other USB cables you may want to try those.
Avoid use of USB 3.0 ports too and stick to USB 2.0 ports as USB 3.0 is known to cause issues.

I tryied more than one cable on more than one computer in more than one USB ports, still dont work.
the thing is, it worked perfectly and then stopped completly.
I’ve updated the software and still it wont work.

You seem to have done most things already.

You could try re-install the drivers (as Administrator)

This is only a suggestion but seeing as there have been a few posts recently about Arduinos loosing the bootloader or it becoming corrupt somehow maybe reload the bootloader.

Gonna be away for a couple days if anyone else wishes to help out too ?

Stupid question...
re-intalling the drivers means to re-install the arduino software?
I'm not sure what you mean by bootloader :frowning: