The error message http error 503 the service is unavailable occurs in the system when you want to visit a site in online or offline mode. If you are working on local host and developing programs but the server is not on then you can also get this error. HTTP is a protocol which is used in communicating with server. If the application pool is paused or disabled then you can get this error. In this situation the web server is currently unable to handle http request. It is the foundation of data communication for www.Http stands for hypertext transfer protocol. Since it is a protocol so it provides rules and regulation of the internet. It is specially designed to improve or enable client and server communication. When client send request it goes to the server through http protocol and after processing this request server send the response. If web server is unable to handle the http request then it gives this message. This error occurs in browser during sending request and it can be occurred in any windows versions. You can get this error during working on php, asp.net server site languages. During working on such type of language we need server for local host. If you have written the programs and executing but the server in not on or busy then it will also gives the error.
Cause of http error 503 the service is unavailable:-
The main cause of http error 503 the service is unavailable is server is unavailable when you are trying to access the web page. This is a common problem for users. If the server is too busy to load your requested page or maintenance being performed on it then you can get this situation. For working on web page or surfing on the internet or sending the client request to the server it is compulsory to available the server because request performed by the server and give a response against the request. If server will unavailable then it will not support you to visit the web page or other URL.
Solve http error 503 the service is unavailable:-
You can solve http error 503 the service is unavailable by refreshing the web page or checking that when you are requesting to the server then that time server is available or not or is it too busy. Wait for a while and try again But if you are working on local host and getting this error then go to the server option you have installed in your system and on it. Ex- if you are developing a website on php and trying to check it on local host then start the server then try to access the web pages. Follow the other steps to fix this problem-
i) Look for the selected website after opening the IIS.
ii) Go to the application pool and select it
iii) Right click on the application pool select “Start”