Error Codes

GetLastError() - the function that returns codes of error. Code constants of errors are determined in stderror.mqh file. To draw the text messages use the ErrorDescription() function described in the stdlib.mqh file.

Error codes returned from a trade server or client terminal:

Constant	Value	Description
ERR_NO_ERROR	0	No error returned.
ERR_NO_RESULT	1	No error returned, but the result is unknown.
ERR_COMMON_ERROR	2	Common error.
ERR_INVALID_TRADE_PARAMETERS	3	Invalid trade parameters.
ERR_SERVER_BUSY	4	Trade server is busy.
ERR_OLD_VERSION	5	Old version of the client terminal.
ERR_NO_CONNECTION	6	No connection with trade server.
ERR_NOT_ENOUGH_RIGHTS	7	Not enough rights.
ERR_TOO_FREQUENT_REQUESTS	8	Too frequent requests.
ERR_MALFUNCTIONAL_TRADE	9	Malfunctional trade operation.
ERR_ACCOUNT_DISABLED	64	Account disabled.
ERR_INVALID_ACCOUNT	65	Invalid account.
ERR_TRADE_TIMEOUT	128	Trade timeout.
ERR_INVALID_PRICE	129	Invalid price.
ERR_INVALID_STOPS	130	Invalid stops.
ERR_INVALID_TRADE_VOLUME	131	Invalid trade volume.
ERR_MARKET_CLOSED	132	Market is closed.
ERR_TRADE_DISABLED	133	Trade is disabled.
ERR_NOT_ENOUGH_MONEY	134	Not enough money.
ERR_PRICE_CHANGED	135	Price changed.
ERR_OFF_QUOTES	136	Off quotes.
ERR_BROKER_BUSY	137	Broker is busy.
ERR_REQUOTE	138	Requote.
ERR_ORDER_LOCKED	139	Order is locked.
ERR_LONG_POSITIONS_ONLY_ALLOWED	140	Long positions only allowed.
ERR_TOO_MANY_REQUESTS	141	Too many requests.
ERR_TRADE_MODIFY_DENIED	145	Modification denied because an order is too close to market.
ERR_TRADE_CONTEXT_BUSY	146	Trade context is busy.
ERR_TRADE_EXPIRATION_DENIED	147	Expirations are denied by broker.
ERR_TRADE_TOO_MANY_ORDERS	148	The amount of opened and pending orders has reached the limit set by a broker.

MQL4 run time error codes:

Constant	Value	Description
ERR_NO_MQLERROR	4000	No error.
ERR_WRONG_FUNCTION_POINTER	4001	Wrong function pointer.
ERR_ARRAY_INDEX_OUT_OF_RANGE	4002	Array index is out of range.
ERR_NO_MEMORY_FOR_FUNCTION_CALL_STACK	4003	No memory for function call stack.
ERR_RECURSIVE_STACK_OVERFLOW	4004	Recursive stack overflow.
ERR_NOT_ENOUGH_STACK_FOR_PARAMETER	4005	Not enough stack for parameter.
ERR_NO_MEMORY_FOR_PARAMETER_STRING	4006	No memory for parameter string.
ERR_NO_MEMORY_FOR_TEMP_STRING	4007	No memory for temp string.
ERR_NOT_INITIALIZED_STRING	4008	Not initialized string.
ERR_NOT_INITIALIZED_ARRAYSTRING	4009	Not initialized string in an array.
ERR_NO_MEMORY_FOR_ARRAYSTRING	4010	No memory for an array string.
ERR_TOO_LONG_STRING	4011	Too long string.
ERR_REMAINDER_FROM_ZERO_DIVIDE	4012	Remainder from zero divide.
ERR_ZERO_DIVIDE	4013	Zero divide.
ERR_UNKNOWN_COMMAND	4014	Unknown command.
ERR_WRONG_JUMP	4015	Wrong jump.
ERR_NOT_INITIALIZED_ARRAY	4016	Not initialized array.
ERR_DLL_CALLS_NOT_ALLOWED	4017	DLL calls are not allowed.
ERR_CANNOT_LOAD_LIBRARY	4018	Cannot load library.
ERR_CANNOT_CALL_FUNCTION	4019	Cannot call function.
ERR_EXTERNAL_EXPERT_CALLS_NOT_ALLOWED	4020	EA function calls are not allowed.
ERR_NOT_ENOUGH_MEMORY_FOR_RETURNED_STRING	4021	Not enough memory for a string returned from a function.
ERR_SYSTEM_BUSY	4022	System is busy.
ERR_INVALID_FUNCTION_PARAMETERS_COUNT	4050	Invalid function parameters count.
ERR_INVALID_FUNCTION_PARAMETER_VALUE	4051	Invalid function parameter value.
ERR_STRING_FUNCTION_INTERNAL_ERROR	4052	String function internal error.
ERR_SOME_ARRAY_ERROR	4053	Some array error.
ERR_INCORRECT_SERIES_ARRAY_USING	4054	Incorrect series array using.
ERR_CUSTOM_INDICATOR_ERROR	4055	Custom indicator error.
ERR_INCOMPATIBLE_ARRAYS	4056	Arrays are incompatible.
ERR_GLOBAL_VARIABLES_PROCESSING_ERROR	4057	Global variables processing error.
ERR_GLOBAL_VARIABLE_NOT_FOUND	4058	Global variable not found.
ERR_FUNCTION_NOT_ALLOWED_IN_TESTING_MODE	4059	Function is not allowed in testing mode.
ERR_FUNCTION_NOT_CONFIRMED	4060	Function is not confirmed.
ERR_SEND_MAIL_ERROR	4061	Mail sending error.
ERR_STRING_PARAMETER_EXPECTED	4062	String parameter expected.
ERR_INTEGER_PARAMETER_EXPECTED	4063	Integer parameter expected.
ERR_DOUBLE_PARAMETER_EXPECTED	4064	Double parameter expected.
ERR_ARRAY_AS_PARAMETER_EXPECTED	4065	Array as parameter expected.
ERR_HISTORY_WILL_UPDATED	4066	Requested history data in updating state.
ERR_TRADE_ERROR	4067	Some error in trade operation execution.
ERR_END_OF_FILE	4099	End of a file.
ERR_SOME_FILE_ERROR	4100	Some file error.
ERR_WRONG_FILE_NAME	4101	Wrong file name.
ERR_TOO_MANY_OPENED_FILES	4102	Too many opened files.
ERR_CANNOT_OPEN_FILE	4103	Cannot open file.
ERR_INCOMPATIBLE_ACCESS_TO_FILE	4104	Incompatible access to a file.
ERR_NO_ORDER_SELECTED	4105	No order selected.
ERR_UNKNOWN_SYMBOL	4106	Unknown symbol.
ERR_INVALID_PRICE_PARAM	4107	Invalid price.
ERR_INVALID_TICKET	4108	Invalid ticket.
ERR_TRADE_NOT_ALLOWED	4109	Trade is not allowed.
ERR_LONGS_NOT_ALLOWED	4110	Longs are not allowed.
ERR_SHORTS_NOT_ALLOWED	4111	Shorts are not allowed.
ERR_OBJECT_ALREADY_EXISTS	4200	Object already exists.
ERR_UNKNOWN_OBJECT_PROPERTY	4201	Unknown object property.
ERR_OBJECT_DOES_NOT_EXIST	4202	Object does not exist.
ERR_UNKNOWN_OBJECT_TYPE	4203	Unknown object type.
ERR_NO_OBJECT_NAME	4204	No object name.
ERR_OBJECT_COORDINATES_ERROR	4205	Object coordinates error.
ERR_NO_SPECIFIED_SUBWINDOW	4206	No specified subwindow.
ERR_SOME_OBJECT_ERROR	4207	Some error in object operation.