gwotang
Is F:\ a removable drive or a regular hard drive?
Do you have "Generic shell icons" checked? If not can you please try checking it and see if it makes any difference.
If this change has no effect then do you have "Overlay icons" checked? If you do can you please try unchecking it and test.
I suspect that checking "Generic shell icons" will most likely either solve the problem or make it worse with all files having folder icons.
The file icons are retrieved using a background thread and until the actual icon is retrieved a temporary icon is used in its place, this temporary icon happens to be the generic shell icon.
Please let me know and I will do some more research on this.
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