Do I need to keep the external hard drive always on?

3.5drives require 12vdc at no less than 2 amp recomended 12vdc 3amp it is always best to provide more amp for hard drive keep the voltage correct 12vdc
asme adaptors work out to 4 gig drives all my Western digital drive have same power adaptor no matter the Gig size .

Leave it connected to your computer and try a restart.
If the folder is still showing as empty, power down the computer then disconnect the external drive.
Power on the computer and connect the external hard drive to a different usb port.
I had this exact problem with a 1000 Gb external drive that was full of movies and music. I thought it had all been lost .. After 2-3 days and repeated attempts of restarts and power-downs/different usb ports it suddenly was recognised again and has worked perfectly since

Try out the hard drive on another computer, to verify if it's a hard drive issue or a computer issue. Then, get another hard drive, or USB stick, and try reading/erasing/recording on it from your MAC, to see if the computer is handling external data storage devices properly.
I'm not a MAC guy so I can't help out if it's your computer that's misbehaving... but if it's the hard drive that's misbehaving, then you may want to run a partition repair scan and also run a surface-level scan to make sure everything's ok. If you have a PC near by, get the WD Diagnostic utility here http://www.softpedia.com/get/System/Hard-Disk-Utils/Western-Digital-Data-Lifeguard-Diagnostics.shtml and run an extended disk test. This will find and repair any logical problems with the hard drive. After the test is over, run a SMART scan too, that will tell you the physical state of the hard drive. If it points to some parameters that are off the recomended values you may want to get all the data off the drive. I'm sorry to say, but the 500GB-1TB Western Digital hard drives, especially the Green Line series, proved to be a very silky line, fragile, unreliable.
If you opt for a new hard drive, I suggest that you keep the WD casing, and stick a Samsung or a Seagate hard drive.

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I recomend to you to buy an external HD with 1TB for less than $100.00. in Comp Usa web page

Iomega Select 34966 1TB External Desktop HD
Iomega Select 34966 External Desktop Hard Drive - 1TB, 3.5", USB 2.0, 480Mbps
Only $74.99

INFO:
Files are never really erased from a hard drive.
At various stages files are always recoverable.

RECOMENDATION:
To truly erase your hard drive take it out and completely destroy it down to many small parts.

Reformat the hard drive.




Hope this tip helps.

r/
David

As long as the activity light is not on/flashing and all programs using the drive are closed, it is OK to unplug the drive. If you want to be on the safe side, turn off the computer, then unplug the hard drive.

use proper drivers as recomended,you nust have the cd rom that comes by default with drive you have

right click on my computer --> manage --> disk management and re assign the drive letter.

If you want something that will always make it keep the same letter there is USBDLM :

http://www.uwe-sieber.de/usbdlm_e.html

Personally I always leave them on. I seem to have had less problems that way.

You should still back up the really important stuff to something ie DVD etc.

It's not IF a HD will fail its WHEN.

I'm still using a 5YR old Lacie drive...

keeping hard drives running will cost more on electric and heat generated from drives as I've found out on of my 160gig sata drives burnt out because I was using pc 24hrs aday and night if I had put a cooler on the bottom it would have lasted 5 years but I only lasted 8 months you can give your hard drives 2 twice or even 5 times life span if kept at room temperature listen to you own advice it's your data and hard drives do what you wish I'm only her for advive you can tak itor leave it