Nice question! Maybe not so nice an answer?
Hi Helene! Thanks for allowing us to assist with your issue.
So that I understand what's happening, you've got an external drive (I'm assuming it's a USB drive?) that you back-up your system to.
There are a couple things to check first. The drive most likely came with software, which you would have installed so that the buttons work. Check to make sure (with the manufacturer) that the software is still current. Often, an update (either by Microsoft or some other software vendor you have) may have disabled the functionality of the device. Hit the websites in question and check.
There are a couple system things we can check, too...
First step is to actually check to make sure it's plugged in, both to power - if applicable - and to the computer itself. Be sure to disconnect it, and then reconnect it to make sure it shows up.
Right-click "My Computer", and select "Manage". In the window that pops up, select "Devices" in the right hand pane. That will list the devices your computer *thinks* it has attached. Look for any yellow question marks. Those are devices it doesn't understand how to talk to.
If the above steps don't work for you, try:
- Control Panel
- If System isn't available, you may have the new look, so hit the "Performance and Maintenance" link, then look for "System"
Hit the "Hardware" tab, then click the "Device Manager" button. Again, look for the question marks.
If there are no question marks, check also for anything with a red "X" on it. That indicates a device with a problem. If your external drive is listed in either of these categories, that's something to look into. My first step would be to disconnect the drive, remove the software, and start again with it.
If you don't have any devices with issues listed, then we go on. Can you see the drive listed when you open "My Computer"? It should be listed as a drive you can access. If it's not, it's possible the drive is conflicting somewhere with regards to the drive letter. To check this is really pretty simple:
Get into System Management again (Right-click "My Computer" and select "Manage"). Down the list under "Storage", select "Disk Management". The system should tell you the drive is there, in the bottom on the right, and what drive letter it is. If you have a drive letter in the "My Computer" window that *should* be your external drive, but isn't, this is where you fix it. Right-click the drive in the bottom, right window you want to change, and select "Change Drive Letter and Paths...". As an aside here, you should set your permanent disks further down the alphabet than your removable, but be sure and leave "C" alone!
Well, that was all in an effort to fix it, and make it work correctly. Now to answer the rest of your question...
Yes, if the drive itself is indeed dead, then you can swap it out. Regardless of the box it came in, WD provides more than a 90 day warranty with it's products. Open the case - if you're sure it's dead - and merely look at the drive. Then head to WD's warranty support website (http://support.wdc.com/warranty/index.asp) and click the "Warranty Check" link on the left. You'll need the serial number on the drive itself (not the housing it came in). They'll quickly tell you whether it's still covered or not. Most of them have 1 or 3 year warranty's, so most likely, you'll be OK.
There are a couple programs there to help you figure it out and check the drive itself, but those also require you connect it to your computer to test. If you're not comfortable with opening your case and hooking it up, ask a friend for some help. Many people will be happy to assist for nothing more than a glass of water...or milk and cookies
The programs they'll ask you to run take a while to run, so download them, and get the instructions all ready before you ask for the help. You'll be much more prepared that way. Then run the tests WD wants you to run, and once you've got an error code, you can go back to the support page and ask for an RMA.
Unfortunately, if the drive is indeed gone, it's unlikely you'll get any data off it without spending a great deal of money. There are some companies that can recover data from dead drives, but they're not cheap, and I'm sorry, I don't have any links to give you.
Hopefully, this is enough information to at least get you started in the right direction.