My Sharpen AI Plugin for Lightroom is Not Working

How to Reset Your Sharpen AI Plugin for Lightroom

If your Sharpen AI plugins has stopped opening after invoking Edit In > Topaz Sharpen AI in Lightroom, please follow these steps exactly. This process will clear your Sharpen AI preset(s) and allow you to re-establish the preset from scratch. Each step is critical and should be followed exactly.

Open Lightroom and go to Lightroom Classic > Preferences and then find the External Editors tab within the new window that pops up;
Click on the Preset box to find the Sharpen AI preset
Make sure that the Sharpen AI preset has a check-mark next to it, and then click Delete preset "Topaz Sharpen AI"...
At this point, you can then click the Clear button -- ensure that you can now see text that says < not specified > to the left, and then close Lightroom completely
With Lightroom closed, launch Sharpen AI from your Applications folder and then close it again once it has fully loaded
Re-open Lightroom, command-click (right-click) a photo and you should see Edit In > Topaz Sharpen AI appear once more

Lastly, if this still doesn't work, and you have your Lightroom Catalog installed to an external drive, please follow the instructions in this video:

How to Delete and Manually Install Your Lightroom External Editor Template