What's the reason maybe to my server?

The site runs ok some days. but today it can’t load the css, imge,js file. the link is right. but can’t access.(when i copy the css link to the address bar and access it,it shows 404).

the environment:

php+linux+apache+mysql
what’s the reason maybe of my server?

Posting the URL would be helpful.

RED,

“Missing Support Files” is something I’ve warned you about more than a year ago. Please re-read the tutorial article linked in my signature for the answer.

Regards,

DK