I can't seem to get any plugins to install anymore. I've tried clicking add new plugin, search and then click install now, I've tried clicking details and then install, and I've tried uploading the files. It either gets stuck at unpacking the plugin or gives me the message "Fatal error: Maximum execution time of 10 seconds exceeded in /home/a5991106/public_html/wp-admin/includes/class-wp-filesystem-direct.php on line 172". It still installs it when I get the error, but won't activate it because it states there is a fatal error.
I tried deactivating plugins I had activated and deleted others I'd installed and found I didn't need but it hasn't helped.
How can I stop the error and get plugins to start installing properly again?