Hello I use plugins to add favicon, it found it but it doesnt work if I add it , refresh browser and no favicon ? what is the problem ?
Which file are you uploading? It should be .ico file. Just upload .ico file in the root directory (where Wordpress is installed), then Ctrl + F5 to force refresh in your web browser.
Try another browser. If the favicon will not be visible, then there is probably something wrong with it.
Try clearing your browser cache, then refreshing. If it's still not there FTP to your host directories and try and find the file to make sure it's in the right place.