I have a major issue, I was doing some modifications to our portal and accidentally I modified the custom default master page and then the portal has totally stopped giving the below error message:
Server Error in '/' Application. The resource cannot be found. Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Please review the following URL and make sure that it is spelled correctly.
Requested URL: /en/Pages/default.aspx
Please I need your help urgenlty as this is our production system and all of our work have delayed.