O365 mail backup failing after adding the additional application ids and shared access node.

Hi @Azhwar  Its hard to say exactly with just this log cut. Adding additional apps and access node should not have any effect on the backup failing. unless the new node had issues accessing the job results share DIR.

Also make sure your access nodes are fully patched on latest MR there have been some changes on MS side and fixes released for this on CV.

If still having trouble open a case and support will assist with finding RCA.