Step by step instructions:
1. Go to
Control Panel >
Network Connections (In classic view).
You should have two connections, one is your network card, the other your 3G modem.
At this point, you can run the Network Setup Wizard by choosing
Set up a home of small office network. Internet Gateway is an option here:
If you want to proceed manually without the wizard:
2. Right click the connection that provides the internet connection and go to "Properties"
3. Click the Advanced tab and tick
Allow other network users to connect through this computer's Internet connection.
4. ... Profit? ... You may need a restart, but it should now work!
If you are having problems, it is possible your 3G stick uses a third party (crippled) driver/dialler program. In this case, all I can suggest is to uninstall it and manually install the generic (Huawei (Most likely)) driver, and adding it as a modem, effectively bypassing the dialler program. You may need to do a search for your providers codes/dialling numbers.