Ever since I installed WordPress 4.0 on my Multisite, I've been having troubles installing and updating plugins.
After I click 'install' or 'update', it gets to the initial downloading part but just hangs there and goes no further. But if I then click on the Plugins panel, it has actually installed it but didn't tell me or show anything. This isn't much of an issue with one plugin but when I'm updating multiple plugins then it only installs/updates the first one.
There are active users on the multisite part so I can't just reinstall WP in case it messes their sites up.
Here's a screenshot of how far I reach: http://workfortheweb.com/wp-content/uploads/2014/10/Update_Plugin.png