This can happen in some cases like local machine installation where it can’t download and install the plugin locally. In that case, simply set permission for the htdocs or the site folder to www-data.
However, if you are using a managed WordPress hosting, like GoDaddy (not a big fan), that may be because of how the system is set up.
Luckily, the solution is very simple.
UPDATED Jan 12, 2018
Add these lines after everyting in your
wp-config.php file via ftp:
define('FS_METHOD', 'direct'); define('FS_CHMOD_DIR', (0705 & ~ umask())); define('FS_CHMOD_FILE', (0604 & ~ umask()));
Make sure there are not PHP errors. Now try again, this should be fixed. If you cannot add those lines, contact Support and they will add it for you.
Good luck getting into chat with them though.
Other things you can do:
Simply go to your GoDaddy sites panel, select the site you want to manage. You should see this:
Use this updater instead.
Make sure to create a backup of your site before doing this. Sometimes this has caused 500 errors in sites because of broken downloads. But, it is lightning fast.
I have a post up about backup if you are curious: How to set up automatic Cloud Backup of your wordpress site using UpdraftPlus and Google Drive