Forum Discussion
evgeni
May 04, 2026Copper Contributor
Exchange Online: Sudden mass quarantine of legitimate emails (tenant‑wide impact)
Hello, Since last Thursday , we have been experiencing a sudden and significant increase in quarantined emails across our Exchange Online tenant. Key observations: - Hundreds of legitimate e...
May 05, 2026
I haven't heard of anything yet but will keep an eye out. Has the DNS changed lately? That could be one reason, seen that before.
- Duncan RobertsonMay 06, 2026Copper Contributor
We are seeing the same. It is quite frustrating. No DNS or O365 email config changes.