cannot open *.kmerFreq file after pregraph, then exit

[cqh1]

My command:

SOAPdenovo-63mer all -s config_file -K 31 -R -o soapdenovo_asm 1>ass.log 2>ass.err

config_file:

max_rd_len=100 [LIB] avg_ins=200reverse_seq=0 asm_flags=3 rd_len_cutoff=100 rank=1 pair_num_cutoff=3 map_len=32 q1=/mnt/hgfs/ubt22share/2.HQdata1/data/CDC012_R1.fq.gz q2=/mnt/hgfs/ubt22share/2.HQdata1/data/CDC012_R2.fq.gz