It seems that the same error happens even after I remove that line. See the output below: Running MG5 in debug mode No module named madgraph.interface.extended_cmd No module named madgraph No module named madgraph.interface.extended_cmd No module named madgraph ************************************************************ * * * W E L C O M E to * * M A D G R A P H 5 _ a M C @ N L O * * M A D E V E N T * * * * * * * * * * * * * * * * * * 5 * * * * * * * * * * * * * * * * * * VERSION 5.2.0.0.GM * * * * The MadGraph5_aMC@NLO Development Team - Find us at * * https://server06.fynu.ucl.ac.be/projects/madgraph * * * * Type 'help' for in-line help. * * * ************************************************************ load configuration from /afs/cern.ch/user/a/anlevin/madgraph_beta2/2.0.0beta4/qed_4_qcd_99_ls0ls1_grid/Cards/me5_configuration.txt load configuration from /afs/cern.ch/user/a/anlevin/madgraph_beta2/2.0.0beta4/input/mg5_configuration.txt load configuration from /afs/cern.ch/user/a/anlevin/madgraph_beta2/2.0.0beta4/qed_4_qcd_99_ls0ls1_grid/Cards/me5_configuration.txt Using default eps viewer "evince". Set another one in ./input/mg5_configuration.txt Using default web browser "firefox". Set another one in ./input/mg5_configuration.txt reweight run_01 Do you want to edit a card (press enter to bypass editing)? 1 / reweight : reweight_card.dat you can also - enter the path to a valid card. [0, done, 1, reweight, enter path][60s to answer] > INFO: Extracting the banner ... INFO: process: p p > w+ w+ p p QED=4 QCD=99, w+ > l+ vl INFO: options: INFO: Running Reweight launch INFO: detected model: SM_LS0_LS1_UFO. Loading... INFO: generating the square matrix element for reweighting INFO: generate p p > w+ w+ p p QED=4 QCD=99, w+ > l+ vl ;add process p p > w- w- p p QED=4 QCD=99, w- > l- vl~ ; INFO: Done 492.8 set anoinputs 1 1.000000e-11 INFO: modify param_card information BLOCK anoinputs with id (1,) set to 1e-11 set anoinputs 2 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (2,) set to 0.0 set anoinputs 3 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (3,) set to 0.0 set anoinputs 4 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (4,) set to 0.0 set anoinputs 5 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (5,) set to 0.0 set anoinputs 6 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (6,) set to 0.0 set anoinputs 7 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (7,) set to 0.0 set anoinputs 8 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (8,) set to 0.0 set anoinputs 9 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (9,) set to 0.0 set anoinputs 10 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (10,) set to 0.0 set anoinputs 11 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (11,) set to 0.0 set anoinputs 12 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (12,) set to 0.0 set anoinputs 13 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (13,) set to 0.0 set anoinputs 14 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (14,) set to 0.0 set anoinputs 15 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (15,) set to 0.0 set anoinputs 16 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (16,) set to 0.0 set anoinputs 17 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (17,) set to 0.0 set anoinputs 18 0.000000e+00 INFO: modify param_card information BLOCK anoinputs with id (18,) set to 0.0 Do you want to edit a card (press enter to bypass editing)? 1 / param : param_card.dat 9 / plot : plot_card.dat you can also - enter the path to a valid card or banner. - use the 'set' command to modify a parameter directly. The set option works only for param_card and run_card. Type 'help set' for more information on this command. [0, done, 1, param, 9, plot, enter path] The answer to the previous question is not set in your input file Use 0 value Command "reweight run_01" interrupted with error: InvalidCmd : original card and new card are identical Please report this bug on https://bugs.launchpad.net/madgraph5 More information is found in '/afs/cern.ch/user/a/anlevin/madgraph_beta2/2.0.0beta4/qed_4_qcd_99_ls0ls1_grid/run_01_tag_2_debug.log'. Please attach this file to your report. INFO: Original cross-section: 0.01575033995 +- 3.8231850484e-05 pb INFO: Computed cross-section: quit INFO: storring files of Previous run INFO: Done INFO: