In case you're using TortoiseSVN and the file is already commited, go to your files project folder, right click on the file/folder you want to ignore, TortoiseSVN -> Unversion and add to ignore list. Then you delete the folder/file (click on it and then push DELETE on your keyboard), right click on your project folder, -> SVN Commit... This will delete the folder from the repository.... Now you can create your folder/file again and then it will be ignored.