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Does it still happen in Troubleshoot Mode?

Thanks for your suggestions. Tried all three to no effect.

Does it still happen in a new profile? An easy way to test a new profile is to install Developer Edition and see if it happens there or refresh your existing profile. Make sure you stay signed out of your sync account when testing.

Hey @zeroknight, I appreciate your suggestions, but I'm only marginally technically competent, so I will just move to Chrome for this unique problem. I WAS surprised the error message suggests only Chrome and Safari -- not Edge. And it didn't call out Firefox by name, just "your browser". If anyone else has no problem accessing Dish Anywhere with Firefox, I'd be interested to know. Cheers.