So sometimes when you have permalinks set up and working in you WordPress installation they would break if you convert your site to network (to WPMU).
So the most obvious solution for this is to go to Admin panel and get to Settings -> Permalinks again and set up them the way they were before.
Hey Guys , so i installed WordPress on Centos 7 and it was successful, but then i faced an Error while installing the plugins. The Error was “Unable to locate WordPress Content directory (wp-content”
It asked to connect with FTP , but kept on failing.
Just Give apache permission to www directory and the content beneath it.
[root@itpings]# chown -R apache.apache -R www/ <---
Now Restart httpd
[root@itpings opt]# systemctl restat httpd.service <--
Now Try to download the plugin and should work.