1. Check your operating system, you should be on a supported OS from Mac. Please refer to this End of Life - Mac article if you're unsure.
2. Check that the user you're logged on as is an Admin user and that the account is a 501 account.
3. Click on the Finder, click Applications, click Utilities, then click Terminal: type into the terminal "id -u". The number displayed should be 501.
EDNA needs to be installed on the 501 user's account, if you are getting 502+ that means you are not the original Admin. If the 501 user exists swap to that account. If the 501 user has been deleted you will have to contact Apple support.
4. Check the permissions on EDNA. Right-click EDNA (Go to the Finder click Applications) and click 'Get Info'.
Applications should be listed in alphabetical order
5. Make sure Read & Write is set under the Sharing & Permissions section.
6. You may have to click the lock to change permissions.