Hi
Already posted a couple of questions regarding our Exchange 2010 -> 2016 migration and here's another.
Exchange 2010 SP3 with Rollup 32. Exchange 2016 CU 20
Mail flow is now via the 2016 server.
Staff and IT use OWA to set out of office messages for themselves and other staff.
They are now getting the "Invalid Canary" message when trying to do this. I've seen references to this from years ago which say it's fixed in 2010 SP3, but we already have this installed.
I have also found this link where someone says they have just started getting the issue after installing the recent 2021 Exchange security updates. Our 2016 is a fresh install so would have had these updates installed already.
https://practical365.com/microsoft-issues-critical-security-updates-for-exchange-server/
The second comment on the above link is the same setup as us and no-one replied to the person's query.
I have checked the case of both the owa and ecp URLs and they are all now lowercase. I have also rebooted both servers with no success.
If I change the link in the browser for owa/ecp to the local 2010 servername we don't then get the error. But we can't get staff to do this as they know the mail server by external url.
This could end up being a major issue so I'm hoping there is a fix for this.
Thanks



