I have installed sharepoint site on my local machine with standalone installation. After that i have changed my machine name then my sharepoint site was not opening. Then i revert the changes to original machine name and reinstalled sharepoint but still the same problem. My central administration is not opening. When i try to open central admin it shows 404 page not found error. where all my installation and configuration was successfull. and i also checked the application pool. All pools are in a started state. Please Help....
Renaming a computer with Sharepoint on is never a good idea and even though you renamed it back I suspect a SID is stored somewhere in your config database.
Anyways, running through the Sharepoint Products and Technologies wizard should sort out your problem. I hope you saved your farm pass phrase because this is where you will need it.
I suggest you create your central admin site on a new port.
MSDN has an article about renaming your server for a stand-alone installation: http://technet.microsoft.com/en-us/library/cc261986(v=office.14).aspx
Basically, after you have renamed the server, run in PowerShell:
Pass the new server name in as a parameter.
Make sure you do iisreset /noforce as well.