I am using nginx w/ varnish in front.
This worked perfectly fine for the longest time. Now when the object cache is enabled, I cannot deactivate/activate plugins. Once I disable the object cache, the plugins will update to whatever state (activated/deactivated).
The only way to disable/enable any plugin on my install is it disable object cache, changed the plugin, then enable the object cache.
I have other sites on this server (Linode VPS) that are not exhibiting this behavior. It started about a month ago on one installation that has been using W3 Total Cache for years. I've tried uninstalling and removing the plugin files and re-installing but the problem will not go away.