rm: cannot lstat `/etc/rndc.key': Input/output error

I have a problem with rndc.key, why can't I remove this?

root@l1 [~]# ll /etc/ |grep rndc.key
?--------- ? ? ? ? ? rndc.key
root@l1 [~]# rm /etc/rndc.key
rm: cannot lstat `/etc/rndc.key': Input/output error
root@l1 [~]#