I would like you to test something, try creating another user profile (admin user), and see if that works fine. I’m thinking you are right with the permissions issue, I wonder if your User profile or environment variables are corrupt.

Before check disk I would also download HD tune, to make sure there is nothing wrong with the SSD / HDD. Once installed, open the app and click on health. If anything is yellow or red, you will need to replace your SSD/HDD.

Glad to hear you have a backup in progress!