Question: Can't access old Time Machine backup files
I'm having trouble with my Time Machine backup. I have ended up with two different backups on the same external drive. One is a backup of the current computer I'm using, and one is from my old MacBook.
I'd like to consolidate these down. I've been working on getting my data organized over the past few weeks, backing everything up to the cloud as well as this drive, etc. The problem I'm running into is an inability to access some of the data on my old Time Machine backup.
The Googling I've done leads me to believe I should be able to change the permissions of the locked folder. So I try that.
Problem is I keep getting the error "You can only read" or "You have no access" upon trying to change the permissions. I type in my password when prompted, but nothing happens. So I've just got a ton of inaccessible data in here.
Any thoughts? Tips? I can't figure out what to do here. I've tried creating a new user that has access with no luck as well.
MacBook Pro with Retina display, macOS High Sierra (10.13.3)