I found a bug in function __dbtotal (TOTAL ON ...) if the source file contains a memo field. I don't know why but the memo fields are cutted off from the target database causing a "data type error".
here the modification I made to the source code (dbtotal.prg) from xHarbour (version 0.99.50) at line 128
CurSelect := SELECT()
// r.c. mod: includes memo fields also - 08/02/2006
/*
aNewDbStruct := {}
Aeval( Dbstruct(), { | _1 | Iif( _1[ 2 ] == "M", NIL, Aadd( aNewDbStruct, _1 ) ) } )
IF ( Empty( aNewDbStruct ) )
RETURN ( .F. )
ENDIF
*/
aNewDbStruct := DbStruct()
Now it works for me. Hope it can be useful
Roberto