I 'm developing a web site using php & mysql. There is a functionality which user can upload images for their profile. and Others can view those uploaded images by entering to the particular user's profile page. When user uploading the image in the back end its create a folder name it using userID (ex; user1234) and particular image will be placed to this folder and image path is stored in the DB. when displaying user profile its refer images which has been uploaded (path retrieve from db which has stored earlier). I have tested this using windows platform (WAMP) and worked as I desired. but now I have deploy this web site in a Linux base server(LAMP). problem is now those uploaded images doesn't display in the site. then I check the server and saw images has been uploaded as desired. then I back up those uploaded image folders and delete them from the server. Thereafter after I placed backup image folder again. now its working. Anybody can tell me the reason. why it is not directly referring those images?? .