Crypt a MLE

I try to crypt() few sentences from an mle
   SetAnsi(False)
   C1 := self:oDCmle:TextValue
   C2 := Crypt(c1, cPass)
which I store in a memo file of a dbServer
   Self:oDbSerber:FieldPut(#mMemo, c2)

I try later to read this memo file, and read it into the mle
   C1 := Self:oDbServer:Fieldget(#mMemo)
   C2 := Crypt(c1, cPass)
   Self:oDCmle:TextValue := c2

Unfortunately, many letters are readable. Any idea why?

Many thanks
Henry