CAPTCHA Solver API Error Code Directory
Fast diagnostics and copy-paste code fixes for common error codes returned by 2Captcha, Anti-Captcha, CapSolver, and CapMonster APIs in Python, Node.js, and cURL.
How to Fix ERROR_ZERO_BALANCE in CAPTCHA Solver APIs
ERROR_ZERO_BALANCE is returned when your account deposit has been completely exhausted. The solver API rejects new task submissions until the balance is replenished.
How to Fix ERROR_NO_SLOT_AVAILABLE in CAPTCHA Solver APIs
ERROR_NO_SLOT_AVAILABLE occurs when a solver's worker pool is temporarily operating at 100% capacity and cannot accept new tasks at the base rate.
How to Fix ERROR_CAPTCHA_UNSOLVABLE in CAPTCHA Solver APIs
ERROR_CAPTCHA_UNSOLVABLE indicates that multiple workers attempted to resolve the challenge but failed to find a valid solution, or the target site rejected the verification token.
How to Fix ERROR_WRONG_USER_KEY in CAPTCHA Solver APIs
ERROR_WRONG_USER_KEY is returned when the API key provided in the request does not conform to the required 32-character hexadecimal format or contains invalid characters.
How to Fix ERROR_KEY_DOES_NOT_EXIST in CAPTCHA Solver APIs
ERROR_KEY_DOES_NOT_EXIST is returned when the API key format is syntactically valid (32 characters), but no active account is associated with that key in the database.
How to Fix ERROR_IP_NOT_ALLOWED in CAPTCHA Solver APIs
ERROR_IP_NOT_ALLOWED occurs when account security settings restrict API access to specific whitelisted IP addresses, and your request originated from an unlisted IP.
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