I have MBI-6119M-T2N, when I access the IPMI WebGUI I get the following error on my browswer, 'ERR_CERT_INVALID'. I have tried different browsers such as IE, firefox, Chrome, there is no option to add exception to this IP and access the IPMI WebGUI.
Please first try performing IPMI factory default.
If issue persists, please re-flash the BMC FW to factory defaults.