Time Machine fails to back up Errer.
The OS is on a Thunderbolt3 drive.
I tried all the things you should check like restarting the Mac checking for updatesI everything is up to date ,i have a Seagate 6 tb drive with four Partitions. are on there.
I have tried other Partitions on there and another hard drive i have .And it still comes up with an errer failed to back up.
I also have another Thunderbolt3 drive with a different version of OS and the internal one both back up on the seagate drive .
I have not tried backing up on those two Partions.
What is wrong is there something wrong with the thunderbolt drive or what?
As usual on here i sorted it out myself.
I did a fresh install and upgraded to be Big Sur ,so far i am pleased with it.
Big Sur that is.

The OS is on a Thunderbolt3 drive.
I tried all the things you should check like restarting the Mac checking for updatesI everything is up to date ,i have a Seagate 6 tb drive with four Partitions. are on there.
I have tried other Partitions on there and another hard drive i have .And it still comes up with an errer failed to back up.
I also have another Thunderbolt3 drive with a different version of OS and the internal one both back up on the seagate drive .
I have not tried backing up on those two Partions.
What is wrong is there something wrong with the thunderbolt drive or what?
As usual on here i sorted it out myself.
Big Sur that is.
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