My 2nd Hard drive is missing

Hi again, DragerAZ!

I'm glad this worked for you!
Well, there are two reasons for this issue to happen.
1. If the dynamic drive was transferred from another operating system computer, then it would be seen as foreign by your system.
2. Your case: When you have a dual boot configuration on your computer, it's highly probable that the two operating systems contradict with each other. This confuses the HDD and it doesn't really know which system it belongs to.
Anyways, so once you import the foreign dynamic drive, all the data should be accessible!

Best of luck! Glad I was able to help you out! :)
SuperSoph_WD