Does anyone know what this est-sfs error means?

est-sfs version 2.04 
config_ind 1000000 ERROR 
assign_observed_type:
config_ind >= max_config 0

est-sfs command:

#Run est-sfs:
est-sfs config-file.txt data-file.txt seed-file.txt output-file-sfs.txt output-file-pvalues.txt

est-sfs config file:

n_outgroup 2
model 2
nrandom 10

data-file.txt format:

0,0,0,0 0,0,0,0 0,0,0,0
0,0,0,0 0,0,0,0 0,0,0,0
0,0,0,0 0,0,0,0 0,0,0,0
24,0,24,0       1,0,1,0 1,0,1,0

Any thoughts would be very welcome!