AriaNg Authorization Failed | Fix Login Error Fast

What The AriaNg Authorization Error Means

AriaNg is a browser interface that talks to the aria2 download engine through a remote procedure call, or RPC, endpoint. When the screen shows this authorization alert, the browser tried to reach aria2 but the RPC layer rejected the request because the credentials did not match what aria2 expects.

The error does not mean your downloads are gone. It only means AriaNg cannot log in to the aria2 JSON RPC endpoint. Once the RPC secret, username, password, or token value lines up again, AriaNg connects and your task list appears as normal.

Most setups that show this error rely on one of three patterns. Some use the rpc-secret setting in aria2.conf, some use basic authentication in a web server in front of aria2, and others combine both. AriaNg has fields for each pattern in its settings screen, and the error goes away once every field matches the active aria2 configuration.

AriaNg Rpc Authorization Errors In Context

Aria2 runs as a background process and exposes a JSON RPC interface, often on port 6800 with the path /jsonrpc. AriaNg reads those details from its own settings and keeps them in browser storage. That means small changes to the server, container, or reverse proxy often leave AriaNg pointing at an outdated RPC address or a stale secret.

When that mismatch appears, AriaNg sends a request and aria2 responds with an unauthorized error. AriaNg shows that response as an authorization failed message instead of a more detailed RPC error code. This design keeps the on screen message short, but it means you need to check several possible causes to bring the dashboard back.

Before you change anything, confirm how you installed aria2 and AriaNg. A bare metal installation that reads a local aria2.conf file behaves differently from a Docker image that takes RPC_SECRET and BASIC_AUTH_USERNAME values from env vars. Knowing the path you used keeps the debug steps short and avoids edits in the wrong place.

Most Common Causes Of The Error

In real setups the same small group of issues explains nearly every report of this connection problem. The table below shows those causes and where you can fix each one.

Rpc Secret And Token Problems

On current aria2 builds the RPC secret is the standard way to protect the JSON RPC endpoint. If the value in aria2.conf or in your container settings does not match the AriaNg RPC secret field, every request fails with an authorization error. Even a single stray space, hidden character, or case change stops the login.

Many guides suggest changing the token during upgrades. That advice keeps unwanted visitors away, but it also means AriaNg loses access until you copy the new value into the browser settings. Any time you rotate RPC secrets, plan a short visit to the AriaNg settings page on each browser that talks to the service.

Rpc Address, Port, And Path Issues

Aria2 listens on a specific address, network port, and path. AriaNg needs to match each of those pieces, especially when a reverse proxy or container sits in the middle. A move from localhost to a private IP, or from the default port to a custom one, breaks existing browser profiles that still point at the previous endpoint.

When the address details do not match, some installs show a direct connection error, while others still reach a proxy that replies with a generic authorization failed message. Checking the full URL in your proxy logs or browser network panel gives you a clear view of which destination AriaNg is actually calling.

Proxy, Tls, And Browser Cache Quirks

Reverse proxies and HTTPS bring extra benefits such as encryption and easier domain names, yet they also introduce header and origin checks. A proxy that strips authentication headers or blocks cross origin requests can make a healthy aria2 instance look unreachable from the AriaNg side.

Browsers also keep AriaNg configuration in local storage. If you run one AriaNg page for several aria2 servers, it is easy to carry an old token or port into a new setup and see an authorization failed banner. Clearing the AriaNg profile or starting with a fresh tab that uses a new preset removes that confusion.

If you changed the aria2 configuration file, rotated secrets, or rebuilt a container just before the first appearance of the message, start with the secret or token fields. If the error started right after you moved the service behind a reverse proxy, pay close attention to the RPC address, port, and protocol settings instead.

Fix AriaNg Authorization Failed Step By Step

Work through these checks in order. Each step targets one group of causes and keeps your changes under control.

1. Confirm The Aria2 Rpc Secret — Open your aria2.conf file or container config, find the rpc-secret line or RPC_SECRET variable, and write down the exact value including letter case.
2. Match The Secret In AriaNg — In AriaNg, open the settings panel, go to the RPC section, and paste the same token into the Aria2 RPC secret token field without extra spaces.
3. Check The Rpc Protocol — Verify that the protocol in AriaNg, HTTP or HTTPS, matches the way your aria2 RPC endpoint is exposed by the server or reverse proxy.
4. Verify Host, Port, And Path — Make sure the AriaNg host matches the server name or IP, the port matches your aria2 or proxy listening port, and the path is usually /jsonrpc unless you changed it on purpose.
5. Apply Basic Auth Only When Needed — If you placed AriaNg or aria2 behind HTTP basic authentication, enter that username and password in the AriaNg connection settings; if you did not, clear those fields.
6. Reload AriaNg Cleanly — After saving the settings, reload the AriaNg page, not just the frame, so the browser picks up the new configuration before trying another connection.

After these steps the dashboard should swap from the authorization banner to the normal task list. If the error stays on screen, the problem usually sits in a more specific piece of the stack such as a Docker image, a reverse proxy rule, or a browser side cache.

Use Logs And Browser Tools When Needed

AriaNg hides most low level details, yet both the browser and aria2 keep helpful output. The browser network tab shows the full request URL, status code, and any visible error body that comes back from the server. The aria2 log records RPC connection attempts and can show when a request fails because of a wrong secret or a blocked origin.

If the on screen message stays vague, open these tools in a second window while you reload AriaNg. Watching the requests in real time makes it easier to see whether you are still calling the wrong port, sending an empty token, or hitting a proxy that strips the header before it reaches aria2.

Extra Checks For Docker And Reverse Proxies

Container based setups often pass settings to aria2 through env vars. The RPC_SECRET value becomes the aria2 rpc-secret, ARIA2RPCPORT adjusts the listening port, and BASIC_AUTH_USERNAME and BASIC_AUTH_PASSWORD add a gate in front of the web interface. AriaNg knows how to talk to these patterns, but all of the values need to match exactly.

In a Docker stack, rebuilds or edits to the compose file may change those values or reset the aria2.conf file. That change can happen even when you never opened AriaNg. The next time you load the page, the stored browser configuration still points at the old token or port and the banner appears again.

• Compare Container Env Vars — Review RPC_SECRET, ARIA2RPCPORT, and related variables in your compose file or run command and line them up with the values shown inside AriaNg.
• Inspect Reverse Proxy Rules — Check that your Nginx, Caddy, or other proxy forwards both the AriaNg static files and the aria2 /jsonrpc endpoint correctly, without stripping headers that carry authentication data.
• Align Https And Certificates — If the browser loads AriaNg over HTTPS but the proxy forwards RPC traffic to plain HTTP, make sure mixed content rules are not blocking the calls or forcing AriaNg to use the wrong scheme.

Reverse proxies also add their own layer of access control. A misplaced basic authentication block or an extra header rule can cause aria2 to see an empty token while the proxy thinks access already passed. The result is the same short authorization failed message in AriaNg, even though the real source of the problem lives in the proxy rule set.

Keep Your Aria2 And AriaNg Setup Stable

Once you clear the current prompt, a few small habits make the next maintenance cycle easier. These habits focus on configuration storage and change tracking rather than complex monitoring.

• Store Config Files In One Place — Keep aria2.conf, Docker compose files, and reverse proxy snippets in a version controlled folder so you can see what changed when the error appears again.
• Write Down Rpc Endpoints — Note the correct RPC host, port, scheme, and path in a short text file and keep it near your other service notes so you can rebuild AriaNg settings quickly.
• Use Browser Sync With Care — When you sync browser settings between devices, check that AriaNg is not carrying a token for one server into a different network where a new aria2 instance runs.
• Test After Config Changes — Each time you edit aria2.conf, Docker env vars, or proxy rules, open AriaNg right away and confirm that the dashboard still connects.

Aria2 and AriaNg are lightweight tools with simple configuration files, so mismatches tend to stand out once you know where to look. By matching the RPC secret, RPC address, and any basic authentication layer every time you touch the setup, you keep this dialog rare and short lived. That habit keeps small misconfigurations from turning into downtime later.

Run a tiny test download after each change so AriaNg and aria2 stay in sync.

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