In Easy365Manager, you can enter a number in “Maximum size for sent messages (KB)” to adjust the maximum size of outgoing email messages for a specific mailbox.
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You can quickly locate the setting by opening up properties for a user, selecting the Mailbox tab, and clicking on Delivery Restrictions.
This opens up the following form, where “Maximum size for sent messages (KB)” is found:

In Easy365Manager, the “Maximum size for sent messages (KB)” setting corresponds to the ‘MaxSendSize’ parameter of the Set-Mailbox PowerShell command.
The value entered with the PowerShell command “Set-Mailbox -MaxSendSize” adjusts the maximum size limit for messages:
Set-Mailbox -Identity lene.hau -MaxSendSize 35840KB
The benefit of using this command is that it enables organizations to manage and optimize their email communication by imposing size limits on outgoing messages.
When customizing the maximum send size on a per-mailbox basis, administrators can prevent the transmission of excessively large attachments, which can impact email server performance, network bandwidth, and recipient mailboxes. This helps maintain efficient email flow, prevents unnecessary resource strain, and ensures that email services remain responsive and reliable.
By tailoring the maximum send size to individual mailbox requirements, organizations can strike a balance between facilitating effective communication and safeguarding system performance.