Ok, then it is a simple "pathing" issue preventing Armory from finding the data it needs... by default, Armory will look in the "default" Bitcoin Core installation locations... on windows, this is "C:\Users\[YOURUSERNAME]\AppData\Roaming\Bitcoin\block"
As you have instructed Bitcoin Core to store the blocks data in a custom location, you need to configure Armory to also use this custom location.
You will need to create an armoryqt.conf file and inside it you need to set "satoshi-datadir" to be the same as your Bitcoin Core datadir value:
satoshi-datadir="D:\Bitcoin Core"
You can read more detailed instructions regarding Armory "pathing" here:
https://btcarmory.com/docs/pathingNote that "armoryqt.conf" is just a simple text file and can be created with the text editor of your choice... but you need to ensure that it is named "armoryqt.conf" and not "armoryqt.conf.txt"... it should be created in your "C:\Users\[YOURUSERNAME]\AppData\Roaming\Armory" directory.
If you cannot see the "AppData" folder, you will need to follow the instructions to "show hidden files/folders" here:
https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files