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Hi all,
Today I noted this trouble using MS Exchange OWA
Company is running Exchange Version 15.1 (Build 2507.6)
I wrote an email and the recipient was a distribution group.
This distribution group is made by 210 users.
I tried to expand (I pressed on "+" button) but I could not see distribution group members, in fact I got this error message:
"The list or group you selected can't be expanded because it's too large".
Is there a way to solve it?
Employees use e-mail just from OWA, so I need to solve this issue for OWA client.
If distribution group is smaller I don't get this warning.
Thanks a lot
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Hi! @Federico Coppola
Thank you for your question.
We are currently looking into this issue and will give you an update as soon as possible.
Thank you for your understanding and support.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(137.6, 98%, 23%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EAS%3C/text%3E%3C/svg%3E)
Check if the group was composed of outside organization contacts. It might be some contacts hidden there. Try to unhide and then check.
Hello,
In this moment I did not found any "outside organization contacts" member of this distribution group.
How can check it properly?
In this moment company has got hybrid environment, in other words company is starting to move some mailboxes from on-premise server to Exchange Online.
We don't experiencing this trouble if I use Exchange Online OWA.
Any other suggestions?
Thanks
Hi!
Before using hybrid environment, did the issue also occur on Exchange On-Premises?
The issue occur on Exchange On-Premise server also
Hi! It may be caused by the Exchange's in-design mechanism and cannot wipe out. You can divide the group into two groups, like every group is made by almost 100 users and send the message to them separately to avoid this issue.