Usually the front ones.

If you are getting a message when you plug it in, the machine you are using does not have the correct drivers for your drive. Sometimes older hardware is just not compatible with certain USB drives.

Do you use the same logon account to access local resources at each of the schools? I am thinking that there may be a Domain Enforced, Machine Policy for your account that is being applied when you are at the different locations. If you are not actually logging-in under a school account, then it is not a Policy being applied to your machine.

Do you normally "suspend" or "shutdown" your notebook when traveling between locations?
If you "suspend" at a location that does not allow USB port access and then "wake-up" the notebook at home, do you then have access to the USB Ports, or do you then need to perform a shutdown to gain access?

I am a school photography manager and for whatever reason at these three schools I can't connect to my camera and the bar code reader won't work as well as the ID printer. All the ports just stop working and I get the "not recognized" message.


I tend to leave my computer on most of the time so I don't shut it down before I get to the school usually. So for example I was at Pecos Elem. on Wednesday and the USB ports would not work even after I re-booted twice. I left the computer running but it was closed. I did NOT turn it off before I got home but instantly at my house the USB ports worked again. As I said the computer was never shut down between the school and my house yet I got two completely different reactions from the USB ports. It's been eight months since I was last at this school and had the same problem last spring and last fall. There are two other schools that I have this problem with EVERY time I am there. 98% of locations I do not have this problem.

Hope that helped?

I don't have a reason for the issue, but I think this my help...

Start -> Administrative Tools -> Computer Management
In the left panel, select System Tools -> Device Manager
In the right panel, open Universal Serial Bus controllers
Nothing should have a yellow exclamation point next to it "!".
On the "Universal Serial Bus controllers", right click and select "Scan for hardware changes".
If any host controller is disabled, try to enable it and "Scan for hardware changes" again.

I hope that solves your problem.

I will try it out the next time I am at one of these schools. Yesterday I had to shoot (camera) without the computer and numbered everything then put it in at my house yesterday. It's like doing the same job twice!

Restart

Sometimes, a simple reboot of your computer could solve question like this. Unplug your USB device, wait for a few minutes, then restart your computer and then plug in back in to see if it works.
This is the simplest and the easiest way and it should be the first method that you think of, if this works, then congrats, if not, please read along and find the right method for your computer.

Try a Different Computer

This move is to help you rule out the possibility that the problem could be the situation of your USB device. If it doesn’t work on the other computer either, your device might be to blame. You should probably consider changing a new device.
If you could make sure that your USB device is problem free, please go to the methods below.

Plug Out Other USB Devices

Sometimes having too many USB devices on the machine might create a conflict, which could stop the running of some devices. To avoid possible conflict among the devices, it is suggested that you disconnect other USB devices and see if the device that you intend to use works.
Reference: https://support.microsoft.com/en-in/help/2654149/error-usb-device-not-recognized-when-you-try-to-access-a-usb-external-hard-drive.
http://www.ieeworld.com/windows-doesnt-recognize-your-usb-devices-when-plugged-in/