Create A fieĀ “app_offline.htm” in the root of the site, where hosted.
“app_offline.htm” file size should beĀ larger than 512.
It is use as default page of site.
It allows you to modify/remove the locks from those files and replace them, without the need to do a full IISRESET,
When we publish site through Visual Studio, it use [Users][LoginUser]AppDataRoamingMicrosoftVisualStudio12.0app_offline.htm.
Error : 503 – site under maintenance.