My assumption is
Blue Iris is returning some kind of ungraceful error response to the camera list request, and for some reason UI3 is not able to report the details properly to you.
If you can open the browser dev
tools on the console tab and reload the page, it may happen to tell you. Otherwise if you can use the Network tab to inspect all the
/json
requests, it will probably become fairly obvious what is wrong. But that could be a struggle for someone with no idea what they're looking at.
There's a chance this could be fixed by deleting all stored site data for the hostname that is failing (the hostname being the local IP address). Here's how you could do that with Chrome. Other browsers would likely be very similar.
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