I updated to Tahoe 26.3.1 and now LrC will not come up. I have uninstalled and reinstalled, shut down Mac ane restarted, Ask Adobe for help, etc,, etc,

I finally got an Adobe agent to fix problem.

Hey, ​@Prescott Dale. Welcome to the Lightroom Community. I am sorry for the trouble you've had with this issue.

Did Lightroom close normally the last time it worked, or is this a fresh installation on this machine? Try these steps to get Lightroom to launch:

• Reset Lightroom by holding the OPT + SHIFT when you launch Lightroom and select 'Yes'.
• Ensure Lightroom Classic has the required permissions on macOS: https://adobe.ly/3DyUwsz
• Go to the following location to launch Lightroom via the terminal.
  In Finder > Application Folder > Open Lightroom Classic Folder > Right-click on Lightroom .app > Show Package Contents > Contents > macOS > Lightroom—double-click to open.

Share the log of what you see in the terminal window when Lightroom Launches. 

Let me know how it goes. 

Thanks!
Sameer K

(Type '@' and type my name to mention me when you reply)