MySQL Query Error

Help me please!
Discuz! info: MySQL Query Error
Time: 2008-5-26 3:08am
Script: /index.php
SQL: SELECT username FROM pfans_members ORDER BY regdate DESC LIMIT 1
Error: Table 'pfans_members' is marked as crashed and should be repaired
Errno.: 1194

repaired and imported backup sql :

Time: 2008-5-28 6:22am
Script: /index.php
SQL: SELECT COUNT(*) FROM pfans_members
Error: Can't find file: './photofans/pfans_members.frm' (errno: 13)
Errno: 1017
How I should do?thanks!