1. I start Feecommander;
2. Freecommander is started
3. D:\ is selected in tree, in the panel is displayed ".."" Background color is white. Is see no files or folders listed.
This is strange, are you using default settings? If not, please try it with default settings, more info in the link below ("How to report a bug").
I can see the folders and files in the file list panel, when I click the D: drive in the tree.
I can't get FreeCommander to show combination of both files and folders with normal white background.
OK, so this is a problem, I can't reproduce it, so as I said, try it with default settings (use the way from the link below and your current settings will be preserved, or just unpack the copy of the program, zip portable version to another folder and test it there).
Make sure the quick filter is not active, or another option.
BTW Is it a standard HDD/SSD, not a virtual, cloud drive?
Is it OK at drive C: ?
I think the screenshot with empty file list would be useful, hints are in the same topic, link below, use the first site for screenshots there, it works without registration.