Why is USB internet tethering not working on my office PCs?

I tried to access internet on my office PCs by USB tethering with my Iphone and Andriod phone but it was not working.
USB tethering was successfully working on my home PCs and all my friends' PCs but not on my office PCs.
What settings on my office PCs do I have to modify? I believe that issue is not related to windows OS versions because all the PCs are using the same OS.

Whether you know it or not, initially a driver needs to be installed to be able to access the phone, which is usually automatic in Win7 or newer provided you still have an internet connection when you first connect the phone, and you have permission to do that (for WinXP a driver likely needs to be manually installed).So that depends whether:

1. You have internet access to the driver when the phone is first connected. That may not work if you disconnect from a network before 1st connecting the phone, if your company limits what updates you get when, and/or otherwise limits internet access with a proxy.

2.It may not work if do not have permission to install programs or an overzealous anti-virus program blocks tethering. For example at our office AVG ends up blocking FedEx shipping software from communicating with FedEx or Lexmark scanning software, by quarantining programs or drivers it is unfamiliar with and "thinks" are a risk.

3. For WinXP I needed to manually install a driver from Samsung to even see files on my S3, which I did not realize on my work computer because I had previously installed Samsung's USB driver for a flip phone. But when I tried to use my phone as USB storage to copy a file from another WinXP computer, I needed to install the Samsung USB driver on that computer before that would work.

If you are blocked from installing software, that may also block you from installing a driver for a USB Wi-Fi dongle to use your phone as a Wi-Fi hotspot (unless it is a laptop or other computer that already has Wi-Fi) or might block you from configuring Wi-Fi.