Hi Lincoln,
In the CA IP AdminUI, click on Tools menu, and at left panel Branding option.
Clicking in the CA Identity Portal log, a new page will open, Cancel this page, and besides the Desktop image, a box with name LOGO will be displayed.
Click "Select/Upload" button, you can upload a new logo which should be 190px X 93px
Click Upload and select your image file, click Cancel button from the page where you select the Image, and click Save button at top right corner.
Let us know if it saves the new Logo
Regards,
Ademir