Dear all, A colleague of mine is using the CEM add-on for SPSS 20.0.1. This worked on her computer previously, but as of this week, she gets the following error message for the spss syntax DATASET ACTIVATE DataSet1. CEM TREATMENT=xcohort VARIABLES=xagecat2 xnon_west xnopartner xchildren /OPTIONS K2K. Error in rcem(tr = "xcohort", mvars = list("xagecat2", "xnon_west", "xnopartner", : Cannot create output dataset. Dataset name already exists. spss.errMsg.SpssError: [errLevel 1060] Number of specified cases does not match the slice size. We have tried many things, up to reinstalling the CEM extension. Anyone who has experienced something similar? best, Peter Lugtig Utrecht University, Netherlands Peter Lugtig | Assistant professor Department of Methodology and Statistics | Utrecht University Postal address: Postbus 80.140, 3508 TC Utrecht Visiting: room B.110, Padualaan 14 homepage: www.peterlugtig.com <http://www.pinterest.com/pin/create/extension/>