What MQL4 error 145 means
The official MQL4 runtime table names error 145 ERR_TRADE_MODIFY_DENIED and defines it as “modification denied because order is too close to market.” The requested order change conflicts with the current market distance or broker freeze restriction.
An error-state value is supporting context, not proof that a call failed or a diagnosis of the whole EA. For noncritical API failures, read the return value and then GetLastError, which resets _LastError. Critical errors such as zero division terminate execution, so code after the failing expression cannot serve as a recovery handler.
