External hard drive not working

I have an exrternal hard drive (500gb) that has started making a clicking sound when it turns on, what can i do fix it or is there anything i can do to salvage my data. Can i possibly remove the Disk and move it to a another working external hard drive?

is it a seagate portable thingy? i had the same problem with one of those. i suggest its the power delivering system that fails . 
but i took the HDD out and build it into my pc, its working till today so... try that? or if you have another (.....)to usb converter try that 

If it's clicking, the drive is dead (or near it.) Back your data up and pop another disk into the housing.

thats not always true mine just did not get enough power becouse it was a usb only 500gb external HDD
so when i put it in my pc it worked just fine. for over half a year now. 

its a western digital, the hard drive turns on but it doesnt show up when i turn on the pc so i cant acces my data so how would i go about backing up the data on it. @HelloMrOwl what do mean my "pop anorhwe disk into the housing."

yes than its just broken, nothing to do about it unless you want to spent a fair amount of money and time.