Fatal Error: Class 'mysqli' not found in...

Hello All, I have been using Apache 2, PHP5 and MySQL 4 and 5 for a long time, and recently had to wipe my box due to a virus! Now that I have everything reinstalled, I can NOT get rid of this annoying MySQLi error. I have experienced this before but I can't seem to fix it this time. I have all of the necessary ini file settings, such as # Extension=php_mysqli.dll # Extension_dir = "C:\PHP5\ext\" I do not get any errors on start up from Apache, but in trying to access mysqli I get this fatal error. I have lib_mysqli.dll all over this computer, Windows, System32, System, C:\PHP5, C:\PHP5\EXT\, everywhere. I'm stuck and need help. I uninstalled MySQL 5 and put 4.1 back on and that didn't help either. Any clues? Thanks! Ralph McMinnville