Problem solved. With this command I created a linked table (Back office).
DoCmd.CopyObject , "tblLijstProducten_Kopie_" & Now(), acTable, "tblLijstProducten"
I change this command into
strKopieTabel = "SELECT tblLijstProducten.* INTO tblLijstenProducten_Kopie FROM tblLijstProducten;"
and...