I get an error whenever I'm trying to retag some question: 500 Server Error sorry, system error system error log is recorded, error will be fixed as soon as possible please report the error to the site administrators if you wish Is this a known issue?

I get an error whenever I'm trying to retag some question: 500 Server Error sorry, system error system error log is recorded, error will be fixed as soon as possible please report the error to the site administrators if you wish Is this a known issue?