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Exchange Online Modify Max Attachment file size

Anthony K O365
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I want to modify the Maximum attachment size. The EOL default 10 MB. However, I do not see the -InternalDsnMaxMessageAttachSize parameter in Set-Transportconfig. What PS add-on is needed for this?
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Anthony K O365Messaging Consulting

Author

Commented:
My PS version is 4.0
Most Valuable Expert 2015
Distinguished Expert 2019

Commented:
Attachment limit is 150MB in EO, but that also depends on the client. You cannot increase it past that limit. Info is here: https://technet.microsoft.com/en-us/library/exchange-online-limits.aspx#MessageLimits

InternalDsnMaxMessageAttachSize is different, it only relates to NDR messages.
Anthony K O365Messaging Consulting

Author

Commented:
Ivan,

Unfortunately, this doesn't help with Attachments.
Anthony K O365Messaging Consulting

Author

Commented:
We have Plan 3 (E3) license. Therefore we should be able to increase it to 150 MB, but PS is not showing the parameter.
Most Valuable Expert 2015
Distinguished Expert 2019

Commented:
Again, the default is 150MB. The parameter you are trying to set only affects NDR messages.
Anthony K O365Messaging Consulting

Author

Commented:
Understood. But is it possible to change the Attachment size on EOL, or am I limited to 10 MB?
Most Valuable Expert 2015
Distinguished Expert 2019

Commented:
Seems we're speaking different languages here, the defaults are now 150MB. You can check via:

Get-Mailbox | ft Name,Max*Size

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As noted above, client/protocol limits apply and might reduce this.

To set the limits, use:

Set-Mailbox vasil -MaxSendSize 150MB -MaxReceiveSize 150MB

Open in new window

Anthony K O365Messaging Consulting

Author

Commented:
Sorry for the confusion. I'm able to modify the MaxReceive and MaxSend sizes. It's the Attachment. (Attachments) The parameter  you show only affects the message size, not Attachments.
Most Valuable Expert 2015
Distinguished Expert 2019
Commented:
You can have 150MB attachment, it's only limited by the message size (well and the MIME bloat, so technically 112MB only). I posted the "limits" article above, you can find the details there.

Whether the client will actually allow you to attach such large files is another story.
Anthony K O365Messaging Consulting

Author

Commented:
You are correct. Thank you!
Anthony K O365Messaging Consulting

Author

Commented:
this was helpful. thanks again