The target site.
401 — Unauthorized
The target wants credentials it did not get. Note the difference from 407: a 401 comes from the destination and concerns your account there; a 407 comes from the proxy and concerns your proxy credentials.
A proxy fixes part of this. Rotation causes as many 401s as it solves. Where a login is involved, holding one IP for the life of the session is what fixes it — a sticky session rather than more addresses.
Why it happens
No Authorization header, or an expired token.
A session cookie tied to the IP that issued it — rotating the exit address invalidated the session.
The API key is valid but not for this endpoint or this region.
How to fix it
- Separate the two failures: if curl through the same proxy returns 401 and without the proxy returns 200, the session is IP-bound.
- Pin the exit address for the whole session with a sticky token when the target ties the session to an IP.
- Refresh the token before it expires rather than after the first 401.
FAQ
What does 401 mean?›
The target wants credentials it did not get. Note the difference from 407: a 401 comes from the destination and concerns your account there; a 407 comes from the proxy and concerns your proxy credentials. The target site.
Why am I getting 401?›
No Authorization header, or an expired token. A session cookie tied to the IP that issued it — rotating the exit address invalidated the session. The API key is valid but not for this endpoint or this region.
How do I fix 401?›
Separate the two failures: if curl through the same proxy returns 401 and without the proxy returns 200, the session is IP-bound. Pin the exit address for the whole session with a sticky token when the target ties the session to an IP. Refresh the token before it expires rather than after the first 401.
Will a proxy fix 401?›
Rotation causes as many 401s as it solves. Where a login is involved, holding one IP for the life of the session is what fixes it — a sticky session rather than more addresses.
Other errors
Stop getting 401
Residential IPs across 199 countries, from $7.35/GB — no commitment, no monthly plan.
Get residential IPs →