Hi Nailai,

Welcome to the Community. It looks like your some windows files are corrupt. If you do not have any important data on your computer, you can do a PC restore by following the below link.

http://dell.to/mWfPtU

If you are in the US you can use the below link to request for a OS disc. Otherwise you will need to call Dell Technical Support in your region.

http://dell.to/qmhJXE

Hope this helps.

Thank you

Royan