Disconnect from WIFI@OU and forget the network.
Open Keychain Access, which should be under the Applications --> Utilities folders.
Within Keychain Access, select login under Keychains and Certificates under Category
You are looking for the certificate named access.ou.edu
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Right click access.ou.edu and select Delete
Reconnect to WIFI@OU
You should receive prompts asking for your OUNet ID and password and to verify the certificate