Hi there! I understand you're getting a "Permission denied" message when trying to share Happy Color pictures on your Mac running OS X 10.15.7. Let's figure this out together.

First, can you tell me what method or app you're using to share the pictures? For example, are you sharing directly from the Happy Color app, via email, social media, or another way? Also, did you recently upgrade your OS or make any changes to your permissions settings?

In the meantime, since sharing photos usually involves access to your Photos library on macOS, here’s a step-by-step way to check and fix permissions:

1. Check Happy Color's Access to Photos:
- Click on the Apple menu (top-left corner).
- Go to System Preferences > Security & Privacy.
- Click the Privacy tab.
- Select Photos from the sidebar.
- See if Happy Color is listed and has permission to access your photos. If not, check the box to allow access.
- You might need to unlock the padlock icon at the bottom left by entering your Mac password to make changes.

2. Check Files and Folders Permissions:
- Still under Security & Privacy > Privacy.
- Click on Files and Folders.
- Check if Happy Color has access to relevant folders like Downloads or Documents depending on where the images are saved.

3. Restart the App:
- Quit Happy Color completely.
- Reopen it after adjusting permissions.

4. Try Sharing Again:
- Attempt to share the picture after these changes.

If Happy Color is not showing up in the Photos or Files & Folders section, or permissions are correctly set but the issue persists, please let me know. We can then try reinstalling the app or checking if there's a recent update that might fix any bugs.

Would you be able to try these steps and update me on what you find? That way, I can guide you further.