You're right Sergey, the memo can have less data than the length of the LEFT command...
Thanks
Jaime

>>As i stated in an answer to Agnes and Sergey, i found the problem. There was a memo field in my select ( i couldn't see it at first because i have more than 40 output fields ), so changing it to left(memofield,...) fixed it.
>
>You better use PADR(memofield,...) or you could get the same error under some circumstances.