Synology Active Backup for Microsoft 365 failing


We purchased a Synology recently to replace our Cloud backup for Microsoft 365. It is running for approximately 3 weeks ago. I was following the Synology guide (increasing the limits on the account, setting up separate tasks, etc.)
There are two problems that I couldn’t solve. I contacted support but they just sent me the same articles that are available online.

  1. Some older accounts are not backing up. I feel this is mostly a licensing issue. I checked them and all of them are archived users. Might be just leftover.
  2. This is my concern. Some Teams accounts are failing. From 68 Teams channel 3 constantly failing. 2 of them are used regularly. This is the error message: “The channel’s site information couldn’t be retrieved via API due to a known issue on Microsoft’s end.”

I tried to look it up on the Teams Admin page, talking with Synology Support. But no luck. I don’t even know where should I look. Probably Microsoft’s side.

Have you ever seen an error message like this?

Thank you!

Just to follow up, it looks like we found the solution with Synology support. This article helped. But it have to be done on all of the channels too.