[Fix] Error creating new button

I looked through the support forums and I saw a bunch of people facing the same issue of being unable to create a new button.

So, what happens is that. You’ll head to to “Visual Editor Custom Buttons” hit “Add New” and when you attempt to add a new post, TinyMCE would fail to load because a javascript resource isn’t found.

(Something similar)
wp-content/plugins/visual-editor-custom-buttons/js/button-1-3.js): failed to open stream: No such file or directory

So what happened is that, you tried to create a button but the the plugin didn’t have enough permissions to create the .js file within

wp-content/plugins/visual-editor-custom-buttons/js

The solution is to ensure that your permissions are correct.
Make sure that apache is the owner of this folder

wp-content/plugins/visual-editor-custom-buttons

This changes the folder user to www-data
chown www-data:www-data -R *
This changes the permissions for all folders to 755
find . -type d -exec chmod 755 {} \;
This changes the permissions for all files to be 644
find . -type f -exec chmod 644 {} \;

https://ww.wp.xz.cn/plugins/visual-editor-custom-buttons/

Credit to Zekth of stack overflow for the above commands!
Source : http://stackoverflow.com/questions/18352682/correct-file-permissions-for-wordpress