For some reason, exe files show up with the 'application' icon. Also some other filetypes like .url (Even though I have chrome installed etc.). Explorer shows fine. But dopus shows blank 'generic' icons 
. This is only when viewing my flash drive.
Uncheck Settings --> Prefs --> Folder --> Folder Display--> Show generic icons for network and removable drives.
Don't know how I missed that, Many thanks