Code #1 is supposed to do the same thing as code #2, but code #1 doesn't work when I run it from my command window. It generates an error message, "File is in use by another", why?

Thank you for your time.

CODE #1.
REPLACE uploaded WITH .T. FOR !RLOCK()

CODE #2.
USE accounts SHARED
DO WHILE !EOF()
IF !uploaded
IF RLOCK()
REPLACE uploade WITH .T.
ENDIF
ENDIF
SKIP
ENDDO