They sell a $70 unlimited plan but cap your tethering after 5 gb. T-Mobile phone data and tethering isn't unlimited. Or, try PDANet+, which consists of a Google Play app and a Windows application that allow you to tether if your phone or provider don't otherwise support it.
If nothing works, check with your cell phone maker - some phone makers have downloadable drivers for Windows that will make the USB tethering feature work.
If you require activation, you'll probably be able to turn on USB tethering but your PC web browser will be directed to a page explaining that you have to pay to activate. It's bundled with my MetroPCS subscription, for example. Note that you may have to pay your cell phone provider to activate the USB Tethering feature. If that's not available, go into Settings, Network and see if there is a USB tethering option there that can be activated. If you see an entry marked "Charging only", tap it and make sure USB tethering is selected. You may need to go into notifications on your phone and make sure USB tethering is activated, as phones will often start in "Charge only" mode and have to be adjusted each time.
Once plugged in, the computer should recognize the phone. You'll want to press "Wifi Direct Hotspot", by the way. It won't show on the play store on some carriers/phones so you may have to get it from ApkMirror. Works amazingly for tethering my iPad up on long car rides so I can watch some Netflix without buffering every 2 seconds. Each platform has a different method for getting it to tether to it correctly. Just make sure you press the little help button in the app (after turning on the direct hotspot it pops up) and it includes instructions for different platforms (Android, iOS, Windows, etc).
There is a way around it on Android by using an app called PdaNet+ but it's a little annoying to use. It was added in I think Android Lollipop. It has its own little channel it goes through. Even turning on a VPN won't get around it because tethering activity is set to not go through a VPN. If your smart phone runs on androids 3.2 or later, it should be automatically detected by PdaNet.Because both Google and Apple added a little flag to any tethering network activity that tells your carrier if you're tethering or not. Please note that this program is only compatible with windows versions before the operating system version 3.2, which is the current version of android and many other mobile devices including smart phones. You will receive a failure or an error code that identifies the issue simply follow the instructions printed on the screen. Just connect your PdaNet enabled smart phone to your computer using the Bluetooth or USB data cable and run the diagnostics test. To check if your PdaNet drivers are working properly, please download the latest version of PdaNet and run a diagnostics test.
Bluetooth Dun is the latest technology designed especially for the PdaNet software and works very well in sync with your PdaNet smart phone.
If you have any other Bluetooth devices such as a USB memory stick, mouse, keyboard or any other items that can act as a connection device with your PdaNet device, all you need is the Bluetooth Dun driver installed on your windows smart phone. The process to synchronize between your PdaNet enabled PDA and your Windows Mobile smart phone are simple all you need is your PdaNet account number for syncing to work. This is a great feature that allows you to keep all your important information in one place and makes syncing your PdaNet device very easy. PdaNet also offers automatic synchronization of your settings and contacts from your PC to your PdaNet enabled smart phone. PdaNet never requires any additional service from you and goes directly through the data plan in your phone. This application enables your cell phone (or laptop) to connect to your Windows Mobile phone via the Bluetooth, Wi-Fi or the USB data cable. PdaNet is actually one of the hottest applications for Windows Mobile based smartphones.