getting ? in permissions when running ll/ls command

I am trying to remove a folder and I am getting

rm: cannot remove ‘...'

when running the ll command I am getting :

> ll ./folder/ 
ls: cannot access ./folder: Input/output error
total 64
drwx------ 1 yehudahs yehudahs    0 Feb 15 23:08 ./
drwx------ 1 yehudahs yehudahs 4096 Feb 27 13:30 ../
d????????? ? ?        ?           ?            ? folder/

any ideas ? using ubuntu 14.10.