What is a 503 Service Unavailable Error (And How Can I Fix It)?

A 503 Service Unavailable Error happens when a web server is temporarily unable to handle a request that’s been made of it. Almost always, the error is on the website itself and there’s nothing you can do about it but try again later. Still, there are a few quick things you can try on your end.
by Yuvraj Wadhwani via How-To Geek