I use the table addcode to generate codes to the table emails.dbf

I am in a network
I received the balloon messagem in the bottom of my windows
"could not save data to file addcode.dbf... etc... etc.."

What happend:
The emails.cod is arealdy 740, but addcode.dbf is still 738
This means that addcod.dbf already got code 740, but is back
to its former 738 value

But it's strange because addcode is not a buffered table !
Please check code below, and help if possible:

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IF !USED("ADDCODE")
USE ADDCODE IN 0 SHARED
ENDIF
SELECT ADDCODE
GOTO 1

DO WHILE !FLOCK()
ENDDO

REPLACE ADDCODE.ID WITH ADDCODE.ID + 1
STORE ADDCODE.ID TO AD_CODE
FLUSH
UNLOCK

replace emails.cod WITH ad_code

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