This document describes how to update your Lehigh password for a wireless connection on a Mac. If you still cannot connect after making these changes, try removing your saved password from the Mac keychain.
If you're not automatically being prompted to enter your new Lehigh password on your wireless connection, you may need to remove the Lehigh wireless network and create it anew.
To do this, click Settings > Network Preferences > Wi-Fi, then click Advanced. Click the Wi-Fi tab.