Make Internal HDD to External

Hey people,

So here's my issue, recently took out my laptop HDD and formatted it, NTFS format, and stored stuff on it. Now when I place that in an enclosure and want to use it as an external HDD drive, it doesnt pick up the device.

Through Diskpart I am able to give the drive a letter and access it, but when I "Safely" remove device, the Drive letters remain....

1St problem, Do I need to do anything special to make the Device a Plug and Play ?
2nd Question, am currently consulting google on the matter, HOW do I remove the Drive Letters that I assigned through Diskpart from "My Computer"

Diskpart isn't the easiest way to do so, and I hope that didn't do anything to the drive. The easiest is to assign the drive a letter in Disk Management. But, to back up a bit, is it recognized in Disk Management, first.