I've had a WD 500G WD5000D032 MyBook Premium for many years and after upgrading to 64-bit Windows 7 Ultimate, I've had the "WD&External_HDD_Button_&_Lights" error in Device Manager since day one and have never been able to correct the problem.
My system drive is all but kaput so I backed up all of my important files and ordered a Crucial 128 GB m4 SATA 6Gb/s SSD with a 2.5" to 3.5" drive converter as a replacement.

Why am I telling you this, honestly, I have no eff'in idea!

Anyway, I'd rather futz around now just in case something I do causes a problem

; then the failing drive will be affected and not the SSD and I can install the 500G WD5000 MyBook Premium in an error-free fashion to the new system drive.
Does anybody have a solution because I don't want to replace a drive that works perfectly fine, except that it runs 24/7 and turns on all by itself after I turn it off. I also don't know if having the yellow warning triangle with an exclamation point in Device Manager will affect the performance of my PC, especially since Windows 7 doesn't recognize my Nikon digital camera either...
Thanks in advance!!!!