If you have separate servers for SharePoint and SQL sometimes you can ping the servers but when SharePoint is attemptiing to create a site, it sits at 42% and does nothing. If you check the logs, the SharePoint server states it cant reach the SQL server. Why? The client configuration isnt set to use IP.
  • Open a command line using CMD.
  • Type cliconfg.exe and press enter.
  • Add IP and check properties to make sure the port is 1433 or what ever the SQL is using.
  • Reset the server.

If you have a failed SharePoint install, delete the SharePoint SQL databases and any Application Pools you created.