If you are upgrading the wordpress version or sometimes one of the plugins you have installed for your wordpress blog and when you upgrade it and refresh the page your upgraded blog page keep showing annoying error “ Briefly unavailable for scheduled maintenance. check back in a minute.” and you refresh it again and again and it keep showing the same thing and sometimes if you refresh the Admin area in wordpress you see the same thing too. Here is the solution for it.
You have to find a file called “.maintenance” without the quotes, this file should be in the root directory of your WordPress installation. DELETE it. Now your blog and your admin area are back to normal.