linker message: ERROR L127: UNRESOLVED EXTERNAL SYMBOL SYMBOL :?C?CSTOPTR MODULE : C:\KEIL\C51\LIB\C51BL.LIB (STRNCPY) this error is present if I only assign a value char to a variable char and a variable far is declared. x.e. f='\0' classic 8051 micro Ver C51 6.20 & 6.23 LIB 4.20 far support enabled