WD MY BOOK, External USB HDD... does not let my desktop start.

Can you go to event viewer and post back the startup error?

Don't want to be a "spoil sport" but I have seen this issue before and there was NO SOLUTION.  I can't say that you won't find one following the link suggested above but sometimes there is a USB/HDD incompatibility that cannot be overcome and the system will never find the OS and boot

Agree with alandc per above.  This is a particular problem with Intel brand motherboards (official Intel motherboards, not general motherboards using Intel CPUs) and I've never found a solution to it.  Updating BIOS to the most recent version doesn't fix it.  The boards just do not like some USB devices, and it's not just storage devices.  I've seen them fail to boot due to USB cameras, hard drives, flash drives and network interfaces.

As I said
I found the problem is the partition that sits in front of the main partition of the My Book Series it cannot be removed only formatted may fix it may not,
 I will never buy a  WD My Book for this reason  and make the WD are just USB drives not the My Book  and have switched to seagate expansion drive 4 terabytes
I still use my WD 2 terabyte My Book but I have getdataback if and when windows won't open it.

My other curiosity is why  changing the bios boot order with a USB drive?
That may hold the key to what's going on here?
rguillermo  what is it your trying to do? Boot off this drive ?
please explain all the problems you're having so we can best help you
Regards Merete

some motherboards change the boot priority to usb , anytime an usb device is connected
i also never found a solution
what motherboard do you have?

Connect a simple usb stick to that PC and then check if it is able to start.mif it is not - then the problem is in BIOS and there no other way to fix it than physically removing usb drive/stick each time when you start the PC.

OK trying all available possibilites..
Will feed back later today...
Thanks

Thanks to all experts !!

yes, but what helped?  what was the solution?

Yes, the details would be helpful.

No success, I just removed the device from a working station and installed it in a station we do not use too much and can be accessed by the LAN.

tx for the update

Then you have accepted the wrong comments! The exact answer was given you here: https://www.experts-exchange.com/questions/28957886/WD-MY-BOOK-External-USB-HDD-does-not-let-my-desktop-start.html?anchorAnswerId=41714968#a41714968 by alandc.

Well I chose the comments that opened doors for me to research before just giving up.

Besides the methods given by my chosen experts do work in some machines...

let me explain I have two mybook Hdd at this customer location where I did the testing.
I used two pcs both exactly the same HP core i3 4 Gb ram win 7
the followed almost all procedures and first machine  did work !! and our customer  reboots it normally since then with the MYBOOK device USB connected.

Only the second HP did not work ..no matter what.... really cant explain why and I ran out of time
so only for the second machine I removed the MYBOOK and located in another station....

So I still have the problem and I am afraid it it returns to the first machine....and cant explain what exactly made the first machine work.

But I am thankful for giving me the possibilities to test.

Thank you for helping me explain better.

you can Always look up the power it uses in disk manager
maybe there's a problem there - one pc delivering less power than the other
that's why using a POWERED USB hub is Always a good idea

**you said it showed a red screen - can you post that?