Hi Mathias, I went through exactly the same issue and I solved it. I was doing some changes on my deployment and decided to reset the config on the device even though I got a warning in the screen from the ISE about this process.
Once I cleared the config using the following command, I started having this issue with any browser (IE, Firefox, Chrome).
Did you apply the command on the device: application reset-config ise?
Based on the TAC Engineer there is no reason identified for this error message so the only solution they suggested was to re-image the device using the link:
http://www.cisco.com/en/US/docs/security/ise/1.0.4/install_guide/ise104_postins.html#wp1158843
BUT, the DVD that came with my ISE Appliance did not work so I had to create a new DVD in order to reboot the ISE and perform the re-imaging (Option 1 - Cisco Identity Services Engine Installation). For this, I had to download the ISO for my version (1.1.3.124) from Cisco.com and create the DVD using ImgBurn. Once you do this, you will need to recreate the certificate for the ISE, reconfigure the Database Admin Password + Database User Password (this 2 parameters MUST be the same for all the appliances in the deployment so you should have available this info at the time of the setup). You also need the DNS domain information, NTP Server IP, DNS IP, Default Gateway, System Time Zone, etc.
I am creating a detailed procedure for this with some screenshots because the information on the Web omits some additional steps.
Important to mention that if your ISE appliance with the issue is the Primary Node for Admin and MNT in your deployment you would have to make some changes on the roles (personas) because you are practically deregistering this node and the database information must be transferred to a new primary node ADM/MNT. Evaluate your situation in order to take the best decision.
By the way, I am using ISE Appliance 3395.
Hope this help you
AC
