USB 3.0 External HDD suddently very slow and random disconnects

Question

I have an external WD 3TB 3.0 USB HDD. I used to have a lot of movies and series stored on it. Recently I tried to clean up what I had on it, and in the process I managed to transfer about 1 TB of movies onto it while removing a lot of series from it.

However I want to transfer the remaining of the series I have on it to another external HDD. At some point yesterday it just randomly started working very slow (between 0 and 750 kb/s). I am trying to get the remaining series moved to my other drive, but when I do it also randomly disconnects which means that I have to start the transfer all over.

I am at a loss of what to do. I have tried performing the same file transfers on another PC and it seems that the problem is the exact same there, which indicates that something is wrong with my drive. How do I fix this?

I googled and some people suggested running a WD Data Lifeguard, but when I try to do that the drive disconnects which results in it not showing up in the results. Furthermore I found some suggestions pointing towards doing a firmware update, so I will try to do that for now and keep you posted.

The drive shows up in device manager but not "My Computer" anymore. EDIT: It suddenly shows up again

Hopefully someone else has a better idea of what I can do to save my drive and all my content. Thanks!

EDIT:

The firmware update was successful and it did decrease the problem a little bit as the drive doesn't seem to disconnect as much as before now. I see a better performance now (355 kb/s - 1.8 mb/s), however it still seems like the drive is disconnecting occasionally or stops the transfer for a few seconds. It is an improvement but it seems like my drive is struggling to perform better, which is should be very able to.

As it seems to be able to maintain a connection I am now doing a chkdsk /r on the drive hoping that will tell me what the problem is. If that doesn't resolve anything I will try to perform a WD Data Lifeguard again.

EDIT!

I wrote to WD Technical Support and got a response. For them to perform an RMA I had to contact one of their partners in my country to do a data recovery and take a screenshot of my DLGDIAG. Once the partner who would do the data recovery contacted WD I would get a new external drive as my warranty was not void.

I left my drive without power for a few days between writing to WD and getting a response and once I tried to connect it, it seemed to work like a charm, but that happiness was short lived. I managed to extract a few episodes and then it was all to hell again. I guess I will reply the lady from WD with the screenshot and contact their partner and hopefully get a proper RMA going. I do however think I will extract as much as possible before sending anything anywhere.

Answer 1

The disk is external, so there are probably two separate devices: the disk and the case (enclosure) with electronics working as USB-to-SATA bridge. You can:

1. dismantle your set and connect the disk internally; or
2. put the allegedly faulty disk into another enclosure (you mentioned another external HDD, it looks like you already have another enclosure).

The point is it may be the enclosure electronics, the USB cable or the power brick that is faulty. Stop using the disk with them immediately and connect it another way as I said. You want to avoid the situation when your attempts to rescue the data damaged it because of another component failing, when the disk itself is perfectly OK.

Only if the problem stands with another connection method, then blame the disk and try to get your data out.