Every time I connect my UNO R3 to my Windows 7 dsktop, I have to install Arduino drivers. Why can't my system recognizes my UNO board?
There could be a few reasons for that.
is it your OWN PERSONAL computer ? If it not your own, you would need to talk to your IT ADMIN to get permissions.
What security do you have installed by way of antivirus / antimalware ? You may need to add some locations to your EXCLUSIONS / WHITELIST
Which version of the IDE ?
Is there any further information you can add to help diagnose the problem ? See the posts near the top of the forum.