sharpening tool paints grey over pixels

[pfn4141]

All of a sudden, could have been after an update - or not - a tool I use with frequency has become unusable because instead of sharpening it seems to be painting grey onto the image.    Photoshop about says it is 24.6.0.   Someone suggested deleting preferences?  I haven't tried that yet.  Do I need to just download it again?   Thanks ahead of time for your assistance!  I do process a fair number of photographs and the sharpen tool is one I use on nearly every photo because I take photos of insects, birds, and plants where I have to enlarge a section of nearly every shot.  I am using Windows 11.

[Jeff Arola]

First thing i would try is to Reset the Sharpen Tool by right clicking on the Sharpen Tool icon in the tool options bar and click Reset Tool.

[c.pfaffenbichler]

Could you please post screenshots with the pertinent Panels (Toolbar, Layers, Options Bar, …) visible? 

What ist the Blend Mode of the Tool (see Options Bar)?