My hard drive is formatted for Mac. When it left St Louis it was working. When it arrived here it is not working. When I plug it in, it shows a green LED. Then it blinks red 6 times then goes back to green.
Any help is greatly appreciated!
DiskWarrior is an superb program, but all it does it rebuild the folders on a Macintosh drive. It does not deal with the hardware or even with the partitions. Since Peter does not say that the system is reporting an error on disc, DiskWarrior will not help.
Look up the blink/error code in your manual.
Kindly mention your HDD brand and model number as External hard drive light/LED behavior varies from model to model. However, I am enclosing Seagate external HDD some basic troubleshooting checks (it is mentioned for Windows, but relevant for Macintosh too and replace the Macintosh equivalent steps instead of Windows). Scroll down and go to the relevant portion of the page: http://knowledge.seagate.com/articles/en_US/FAQ/194531en
Aslo this maybe relevant for you.
How to connect a new external hard drive to your Mac : http://davidtse916.wordpress.com/2007/12/02/how-to-connect-a-new-external-hard-drive-to-your-mac/
The first thing is to check the cable and USB port and use another computer to make sure the Hard drive is working as it should.