Home / HTTP errors / 401 Unauthorized
HTTP error
401 Unauthorized
The request needs valid authentication.
What it means
The server needs to know who is asking, and the request came without valid credentials. Despite the name, this code is about authentication: log in correctly and the same request can succeed.
Common causes
- No credentials were sent
- A wrong username, password or API key
- An expired session or access token
- An Authorization header removed by a proxy
How to fix it
If you are a visitor
- Log in again
- Check your username and password
- Clear the cookies for this site if the login keeps failing
If you run the site
- Check that the token has not expired and is sent in the right header
- Make sure proxies pass the Authorization header through
- Return a WWW-Authenticate header that says which scheme you expect
Catch it before your users do
You can check the status code of any address right now. To hear about 401 errors as they happen, an HTTP(S) monitor requests the page around the clock, compares the response with the status codes you expect and alerts you when it does not match.
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