Time machine gives error "can't connect to a current time machine backup disk"

I suddenly faced this error. But, my time machine’s backup process was fine. The problem was occurred when I tried to run the time machine app to restore a data from previous backups. And the error message always came up.

can’t connect to a current time machine backup disk

So I tried to fix it by rebooting my mac and it doesn’t work. I thought that the networking wouldn’t be an issue to cause this problem. because my time machine was wired to my iMac through thunderbolt.

Folder’s Permission issue

I noticed that the time machine backup folder was not accessible. I tried to change the permission of the folder on Finder. But, it wasn’t possible. So I tried other way which is using Pathfinder app.

And I changed the permission to read the folder and owner of the folder from root to my account. After that the time machine data was finally accessible.

It was great because I could restore my backup which meant I didn’t lose my data. So if you have a problem like this, try to change the permission and the owner of the folder.
I think that if you don’t have Pathfinder app, you can use a command line tool to change them.