Forum Discussion
Exchange Hybrid Configuration Wizard error - root element is missing when connecting to 365
Hi Exchange Brain trust, I have an Exchange 2016 environment where I recently joined a Exchange 2019 server to move everything and eventually decommission 2016 server. Everything is configured m...
Same issue here ever since I moved over to Exchange 2019 CU14. I opened a ticket with Microsoft and they said it might be something to do with the .NET Framework.
This is what they told me, but it didn't help me.
To fix this issue, you can try the following steps:
- Make a backup copy of the machine.config file before making any changes to it.
- Open the machine.config file in a text editor, such as Notepad or Visual Studio Code.
- Check if the file contains any content. If it is empty, try restoring it from a backup or reinstalling the .NET Framework.
- If the file contains content, ensure that it begins with a root element, typically named <configuration> and ends with a closing </configuration> tag.
- If the root element is missing, add it at the beginning of the file, and ensure that all other elements are nested within it.
- Save the changes and restart the application or service that was using the machine.config file.
- CuongT1575
Thanks for the information. Machine.config is a OS level file ? where and which server this should be looked at?This is located:
%windir%\Microsoft.NET\Framework\[version]\config\machine.config
Part of the .NET Framework
During the Office 365 Hybrid Cconfiguration setup, when you run into the "Root element is missing", hit the F12 key to bring up the diagnostic tools, and click on "Open Log File". You can see that it uses the .NET Framework assembly, and it thinks it's missing the root element. But upon checking the machine.config file on a notepad, I can see the opening and closing <configuration> tag, so that means the root element is present.
This issue really started happening when my Hybrid Configuration Wizard updated to the last version. I think it's a bug.
- Curious_Kevin16
Thanks for posting the update. I checked our machine.config and everything looks good as well. I have two separate Exchange 2019 environments and M365 tenants, one for prod and one for test. I can run the wizard find on my test server, but my prod is having this issue.
Both have the same versions of .Net and machine.config files looks the same.
They are even both running the same version of the HCW. I will open a case on our end as well to see where I get.
I'm having same error here.
The hybrid configuration worked till recently, from about 2 weeks ago, user has reported that the mail from O365 accounts are not delivered.
Checking the undelivery report, it shows refused by the on-premise server.
Testing the outgoing connector from O365 to Org server does not go through.
We did renewed certificate recently. Is it the certificate broke the hybrid?
