Tried all of the fixes except new admin user - cannot create new admin user on Government computer. Still not working, Older version of Lightroom 5 still on my computer works fine.
Please ensure you allowed Permission to the folders listed in the article following these steps.
1.- Provide read and write permissions to Application Support and Preference folder on User Library and Hidden Library.
2. - Add user and admin both in permissions.
When you open Get Info option for specific folder .
Make sure to click on '+' symbol , it will open list of user accounts. Add Currently logged in user account and Administrator user account, if it is not added .
Both must have Read and Write access to prevent these kinda issues in future .
Once you had added both Currently logged in user account and Administrator user accounts and provided Read and Write access.
Make sure to Click the Gear icon, and select Apply to Enclosed Item.
Lock and close the Get Info dialog box.
So that all folders present inside Adobe folder will get Read and Write access.
Let us know if that helps