I removed unnecessary code. Try

* Move it outiside of CommanButton, in your application main program.
SET CLASSLIB TO  xfrxlib\xfrxlib, HOME() + ffc\_reportlistener ADDITIVE



* CommanButton
LOCAL lcreport,  loSession, lnRetval, lcPageCaption, loXFFDocument, loViewer
loViewer = CREATEOBJECT("frmMPPreviewer")
loViewer.iTool = 2 && we are using the "fake" toolbar
loViewer.setLanguage("pt")
loViewer.iBook = 2
loViewer.iEmail  = 1
loViewer.VISIBLE = .f.
loSession=EVALUATE([xfrx("XFRX#LISTENER")])
lnRetval = loSession.SetParams(,,,,,,"XFF")
IF lnRetval = 0
	REPORT FORM ("REPORTS\CLIENT1.frx")   OBJECT loSession
	loXFFDocument = loSession.oxfdocument
	loViewer.previewXFF(loXFFDocument, "Astuto")
	loViewer.SHOW(1)
ENDIF

>Hi all
>I buy XFRX and I’m facing the “Fatal error” in my VFP application in this situation.
>I have a print class where I can choose the report I want to print, select a printer, number of copies… tha runs well since a long time ago.
>
>Now I inserted your code like this one below in a Command Button and it runs ok, the problem occurs when I “RELEASE THISFORM” clicking a button… "Fatal error: Exception code=C0000005"
>
>Any ideas would be great.
>Thank’s in advance,
>NPedro
>
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