WordPress Quick Plugin Manager is simple tool allowing you to activate/deactivate WordPress plugins without need to log in and load heavy WordPress admin interface. That is critical when you get in situations that WordPress denies you access to admin section, due to failure in some plugin installation or WordPress upgrade.
Unfortunately, these situations are not rare. If you search Google for ‘You do not have sufficient permissions’ you will find quite a number of help requests regarding this issue and mostly without useful solution or explanation. This error may occur due to various reasons and WordPress itself does not provide any clues which could help finding the right cause for the error.
Most often, problem occurs due to bad behaving plugin. It is easy to solve it if error occurs right after plugin install or upgrade, but if you, for instance upgrade WordPress, it may then trigger misbehavior of one or several plugins,you are denied access to admin section, but you have no clue what plugin causes it.
That is when you may use this tool. It allows you to access plugin activation status without being logged into WordPress, avoiding any possible reason to deny you access. All you have to do is to upload this php script into WordPress root directory and run it using your browser.