Windows 7 will not boot when drive is plugged in

Machine: Dell laptop -Latitude E7240 Ultrabook

External Drive: 3 TB MyBook

when drive is plugged into port replicator-or laptop directly-- the machine will not boot to windows. if the drive is unplugged, the machine will then boot-afterwhich, the drive can be plugged in and is recognized.

How can I get the machine to bbot while the drive is pluggedin–it is not convenient to plug/unplug the drive everytime the machine is booted…

Troubleshooting steps tried already without success:

-looked for legacy USB mode in bios–does not exist

-disabled USB boot in bios

-updated WD SES driver

anyone got any other ideas I can try-----thanks

I would try posting on a Windows forum  http://windowsforum.com/ and see about help. I suspect this may be a newer PC with UEIF and secure boot. I don’t know much about that yet and don’t want to give bad advice about changing anything I’m not familiar with. 

Joe

thanks–yes-those are options in the bios–wasnt sure about changing those settings either…

I have gotten sick of unplugging as well.  I did not see the suggestion, all I see is "thanks-yes-those are options in the bios …  what were the instructions, and did it work?