Thanks you all for your interest in helping me.

The SET EXACT Is set to"ON", i do not use Buffer for this report, the SET DELETED is set to "ON" and i use the variable "NAME" and "DATE" just for this example not in my real code.

A friend of mine told me that if there is a index corruption that can be a cause, that is why i am creating a .prg to index all of my table at the night via a schedule task in WINNT.
I alse trim the "codclie field" in the comparison expresion like this:

ALLTRIM(Table1.codclie) == ALLTRIM(Table2.codclie)

to ensure that it gets the right records.
I am going to prove with this and i will inform you the results later.

If you have another idea, do not you hesitate to let me know...

bye.