when i installed locuszoom sofeware and run locuszoom, there is a error， who can tell me why? thanks!

+---------------------------------------------+
| LocusZoom 1.3 (06/20/2014)                  |
| Plot regional association results           |
| from GWA scans or candidate gene studies    |
+---------------------------------------------+
Traceback (most recent call last):
  File "./locuszoom", line 28, in <module>
    main();
  File "/home/XinkaiTong/software/locuszoom/bin/../src/m2zfast.py", line 1973, in main
    opts,args = getSettings();
  File "/home/XinkaiTong/software/locuszoom/bin/../src/m2zfast.py", line 1250, in getSettings
    find_pos = PosLookup(opts.sqlite_db_file);
  File "/home/XinkaiTong/software/locuszoom/bin/../src/m2zfast.py", line 402, in __init__
    """ % (SQLITE_SNP_POS,SQLITE_TRANS));
sqlite3.OperationalError: disk I/O error