Alternate fix.
Delete everything that looks anything like MySql, Apache and PHP and start over.Try to keep your data and config files. :-)
I'm not making this up. The other fixes suggested didn't work for me but this did. I have been on this since about 8 am and it is now 6:20 EDT
It took about an hour to do the fix, the rest of the time was spent trying the other suggestions and then figuring out what REALLY had to be done. Unless you like reconfiguring Apache, you should probably mv the http.conf file outta the way.
The other fixes probably worked for the other folks. This is what worked for me/ YMMV