Streaming · Plain-English answer
Hulu shows the anonymous proxy error when your IP address appears in a database of known VPN, proxy or data centre ranges. It blocks these because its content is licensed for the United States only. Switching to a different server, clearing cookies and checking for DNS leaks usually clears the message.
Hulu licenses its catalogue for US viewers, so it screens every connection against commercial lists of addresses linked to VPNs, proxies and hosting companies. When your address matches, playback stops with the anonymous proxy message, regardless of whether you are actually in the US.
This is why the error sometimes appears for people not using a VPN at all. Corporate networks, some mobile carriers and household proxies can land on the same lists, and Hulu blocks the address rather than the person.
If you are using a VPN, disconnect and reconnect to get a fresh address, or pick a different US server, since detection is per address rather than per provider. Clear the Hulu app cache or browser cookies so an old session does not contradict the new address.
Then rule out leaks. If your DNS requests escape the tunnel, Hulu sees the mismatch, so run /tools/dns-leak-test/ and fix any leak before trying again. If nothing works, that server range is burned and only a different server will help.
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