How to fix HTTP error 503 service unavailable?

503 error is a temporary error that appears on user's browse when the web page being accessed is temporarily not available because of an error in the HTTP server. Webmasters choose to return 503 error when the server is taken down for maintenance. The cause of 503 error could be different but it's only shown when the server isn't available.

Note that this is totally different from the HTTP error 404 which appears when the page being accessed (or linked to) is permanently deleted from the server and the URL points to a non-existent page.

How to fix 503?

As 503 is related to the server, ensuring the server uptime is the most appropriate way to address this issue. Generally you should check the service status in your web host control panel and check if apache (or whatever server your're using) is running fine. If not, you should attempt to restart it - this fixes most of the errors commonly encountered by a live server.

You cannot fix the problem on someone else's server. I thought you were trying to fix the 503 error on your own server. The website you're trying to access is government of Pakistan's and unless you're the administrator of the website, you won't have access to their server (the http server). The bottom line is that the HTTP errors are caused because of issues / situations on the server side. An end user can't do anything about it apart from contacting the web administrator and letting them know what's wrong.

PS: Always explain the problem and the situation in detail so that it's easier for the rest of us to understand what's the exact situation. In my response, I assumed that you're the administrator of the server and your users are experiencing 503 error on some of the pages.

Recurring an error page with "200 OK" will result in us indexing the change of content like that (and if all of your pages return the same error page, then we may assume that these URLs are duplicates). Redirecting to a temporary page will result in that redirect being used for indexing. It's fine to show text to users on a 503 error page, or use fancy JavaScript, etc.