ftdiusb driver not working

Hi Folks,
I’m on a Mac using 10.5.8. I downloaded arduino and copied it into the application directory and then opened the FTDIUSBSerialDriver_10_4_10_5_10_6 package and followed the install path. Then I restarted and started arduino. But I don’t have a usb driver in the Tools/Serial Port pull down.
Is there something obvious that I’m doing wrong. Can’t even get started. I have used previous versions of arduino, last one, 17.
Fox sends.

Okay folks, I read what some other's had to say, found the search block, searched for answers and wound up fixing permissions with the disk utility, then deleting the FTDI kext, rebooting, reloading FTDI, rebooting, attaching the usb cable to the turned on arduino, and there it was and it reloaded. Thanks for running a robust forum with so many answers. Obviously you are good folk. Thanks much, Regards, Fox sends.