If you experience any of the following, use this document to help troubleshoot the issue:
Unable to access the Internet on my computer using iPhone
Unable to enable Internet tethering on iPhone
iPhone displays "Internet Tethering" whenever I sync my iPhone to my computer or when I connect to my computer for charging
Internet tethering speed is not as fast as expected
Internet tethering connection drops when placing or receiving a phone call
An error message appears after pairing iPhone with the computer using Bluetooth