Karen, it surely does seem as if this ought to be the answer, though it isn't. I found “Show Icon Preview” checked and “Show Item Info” unchecked. 

FYI, in most folders I have a group of image files that display only the generic thumbnail and in some other folders I have a group that are mixed: some display the generic version and others display the image icon. As I turn the two options  of “Show Icon Preview” and “Show Item Info” on and off for the heck of it, then wait for a few moments with “Show Icon Preview” marked, occasionally a fraction of the generic versions will suddenly switch to the image icon while I watch. But not all. And it doesn’t seem to matter whether it is a TIFF file, a PSD, or a JPEG. So I’m not quite at the solution yet.

Lynette

> On Sep 13, 2019, at 3:10 PM, Karen Ackoff <[log in to unmask]> wrote:
> 
> OK, Lynette, try this…
> 
> Make sure you are in the Finder. Go to the View menu and select Show View Options. Make sure Show Icon Preview is checked.
> 
> My guess is you have Show Item Info checked. You can check them both, if you wish. I work with the Icon Preview.
> 
> Let me know if that does the trick.
> 
> K
> 
>> On Sep 13, 2019, at 10:44 AM, Lynette Cook <[log in to unmask]> wrote:
>> 
>> Since upgrading to Mohave I have noticed a problem with image file thumbnails: most of the time I see a generic thumbnail for the file type (JPEG, PSD) - not the image itself. So I can’t remember what a lot of these images are unless I open the file! Anybody know what’s causing this? A Google search indicates that some people fixed the issue by deleting Sketch or a Google app of some kind, yet I have neither of these.
>> 
>> Lynette
>> —
>> Lynette Cook
>> u

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