Welcome 1foxracing .... if it's a more complex problem .... follows Rolo42 request ....
But just in case the obvious has been missed ...........
Assuming these are non-system drives ....and it's all being newly configured
Click start...
Right click "Computer"...
Click "Manager"...
Click "Storage"...
Click "Management"...
If you get in here and the drives are Not registered ..... it will give you a series of prompts including choosing a drive letter ("P", "K") ..... follow these to register the drives into the OS and reboot as requested ..... after the boot..... drives should appear under manager.
Aussie Allan