>WHat is your exact code?

Well, I've got it working now. What I _was_ doing in a form Valid() method:

...
THISFORM.llUseError=.F.
USE mytable EXCLU ALIAS xxdummy
IF !THISFORM.llUseError
do stuff
ELSE
alert user
ENDIF
...

and in the FORM's Error() method:

IF nError=3
THISFORM.llUseError=.T.
ELSE
=DODEFAULT() &&my error handler.
ENDIF

*=============*
When I do it directly in the method, as you suggested, this works:

jcOldErr=ON("ERROR")
jlError=.F.
ON ERROR jlError=.T.
USE mytable EXCLU ALIAS xxdummy
IF !jlError
do stuff
ELSE
alert user
ENDIF
ON ERROR &jcOldErr
*=============*

Don't know why the first doesn't work...

Thanks, Mike.