Files successfully uploaded via FTP but cant be accessed trough browser

I have problems with accessing my php files uploaded successfully, but cant be accessed trough the browser. I see them uploaded on the htdocs folder but when i go to address the directory listing shows only two out of four files. I dont know why this is happening. Are there reserved file names which are forbidden to be shown or something. Moreover i hadn’t set any directory privacy. I had the same problem when i tried to embed javascript file other files where loading perfectly fine but only one had the problem when i changed the file name it loaded well as the others. Here are some pictures to show the problem.
Image of the FTP client
And image of the browser

Chat scripts are not allowed on our hosting, please remove those files from your website.

I didnt know it sorry for that! Thank you for your answer.