Errors Reference

When an error occurs, Smart Proxy Manager sends a response containing an error code.

When using the Smart Proxy Manager API, the error code is returned in the X-Crawlera-Error header, with a human-readable description in the response body.

Errors can be classified into two main categories:

• Bans. These are the errors produced when Smart Proxy Manager couldn’t find enough unblocked IPs, and are plotted in red in the Smart Proxy Manager usage stats.

• Failures. These are all the remaining errors, some of them produced by errors on the user side and other produced by errors on Smart Proxy Manager server side. These are plotted in gray in the Smart Proxy Manager usage stats.

In both of these cases requests don’t count towards your monthly successful quota. Check out Zyte Smart Proxy Usage & Recent Requests to understand more about your Smart Proxy usage.

Note

These error codes are subject to change at any time, so they should not be relied on and only used for debugging.

Ban Errors (Not Enough Capacity)

X-Crawlera-Error	Response Code	Error Message	How to fix or debug
banned	503	All download attempts failed. Please retry.	Trying again usually works. If you keep getting this message, you may need to consider Zyte residential proxies or Zyte API. Please contact support.
noslaves	503	No available proxies to fulfill request. Please contact support.	Trying again usually works. If you keep getting this message, you may need to consider a Smart Proxy Manager Enterprise plan with dedicated capacity. Please contact support.

Failure Errors (User Side)

X-Crawlera-Error	Response Code	Error Message	How to fix or debug
bad_session_id	400	Bad session ID	Create a new session, this one probably expired.
user_session_limit	400	Session limit exceeded	Create less sessions or upgrade your plan.
invalid_request	400	Invalid request (typically malformed)	The client-side technology you’re using with Smart Proxy Manager may have some incompatibilities. Contact our support team for help.
regions_with_sessions_not_supported`	400	Regions with sessions not supported.	Make sure you’re not using X-Crawlera-Region and X-Crawlera-Session together.
bad_uri	401	Malformed URL	Check the URL you’re passing to Smart Proxy Manager. Contact our support team if you need help.
bad_auth	401	Incorrect authentication data	Make sure you’re using the right Smart Proxy Manager credentials.
user_suspended	403	User account suspended	Extend the overage limit in your account through the Billing section
bad_proxy_auth	407	Incorrect authentication data	Make sure you’re using the right Smart Proxy Manager credentials.
max_header_size_exceeded	413	Invalid request. Size of headers above limit of 102400 bytes.	Make sure your headers aren’t longer than the limit.
too_many_conns	429	Parallel connections limit has been reached	Reduce concurrency or upgrade your Smart Proxy Manager plan
header_auth	470	Unauthorized header	You’re using a Smart Proxy Manager header (or header value) that is not allowed in your current plan. Consider upgrading to a higher plan or contact our support team for alternatives.
header_auth	470	X-Crawlera-UA header is no longer supported, use X-Crawlera-Profile instead	X-Crawlera-UA header has been deprecated, use X-Crawlera-Profile instead.
internal_server_error	499	Connection closed by client	Check the timeout used when connecting to Smart Proxy Manager from your code. It may need to be increased. Unlike other errors, this error is not returned in the response, because it happens when the client drops the connection early, without waiting for the response. However, these errors are visible in Dash (Crawlera Stats).

Failure Errors (Server Side)

X-Crawlera-Error	Response Code	Error Message	How to fix or debug
nxdomain	502	Domain not found	Check the domain of the URL you’re trying to fetch, it may be wrong.
ehostunreach	502	Host is unreachable	The domain you’re trying to access may be down. Contact our support team if this is not the case.
econnrefused	502	Targey website is refusing connection	Check the website works in your browser, and contact support it if does.
econnreset	502	Connection with website lost	Trying again usually works. unless the target website is having some issues. If the issue persists, contact our support team.
socket_closed_remotely	502	Target website closed the connection	Trying again usually works, unless the target website is having some issues. If the issue persists, contact our support team.
ssl_tunnel_error	502	Failed to initialize SSL tunnel (This contemplates both client SSL errors trying to connect to Smart Proxy Manager and Smart Proxy Manager trying to connect to target websites.)	Install the Zyte CA certificate. Contact support if you still have issues.
enetunreach	503	Network unreachable	Trying again usually works. If the issue persists, contact our support team.
serverbusy	503	Server busy: too many outstanding requests	Try again after some minutes
cannot_dispatch	503	Service Unavailable	Try again after some minutes
timeout	504	Timeout waiting for a response from the target website	Check if the URL you’re trying to access actually works, contact support if it does.
msgtimeout	504	Timeout receiving data from the target website (after the TCP connection is established)	Check if the URL works well in your browser, and contact our support team if it does.
connect_timeout	504	Timeout establishing secure tunnel to target website	Check if the URL works well in your browser, and contact our support team if it does.
domain_forbidden	523	The domain you are trying to access is restricted in SPM	Contact support to check if the restriction can be lifted
bad_header	540	Bad xheader value	Check the value you passed in the X-Crawlera header and make sure it’s valid according to the documentation.
data_error	541	Response size is too big. The maximum response size in Smart Proxy Manager is 500 Mb.	Fetch a URL that is smaller in size.
bad_endpoint	542	You’re accessing the wrong API endpoint for Smart Proxy Manager.	If you’re on an Enterprise plan, make sure you’re using your Enteprise hostname (eg. acme.crawlera.com).