How to setup an email storage alerts to get admins notified when each individual users mailbox reaches at least 90 percent storage in EXO?

Rule description - EXCHANGE admin MAIL FLOW >> RULES >>

Apply this rule if Is sent to 'Inside the organization' and Includes these patterns in the message subject: 'Your mailbox is almost full' Do the following Blind carbon copy(Bcc) the message to "*****@xyz.com"*

Hi @Vinod Survase ,

Based on my research, so far, I do not find any reference to setup alert emails of users' mailbox storage, or warnings that mailbox is nearly full to admin.

The appropriate way at this moment is to check the status of the Quota chart to verify whether the user's mailbox is healthy or not on the mailbox usage report page.

Reference: https://learn.microsoft.com/en-us/microsoft-365/admin/activity-reports/mailbox-usage?view=o365-worldwide#the-quota-chart

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Using PowerShell

1. Connect to Exchange Online: If you're using Exchange Online (part of Office 365), you'll need to connect via PowerShell:

      powershell
      Copy code
      Connect-ExchangeOnline -UserPrincipalName ******@yourdomain.com
   

   Get Mailbox Sizes: You can retrieve mailbox sizes with the following command:

      powershell
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      Get-Mailbox -ResultSize Unlimited | Get-MailboxStatistics | Select DisplayName, TotalItemSize | Where-Object { $_.TotalItemSize.Value.ToGB() -gt 30 }
   

   This command lists all mailboxes over 30 GB.
2. Send Alerts: You could create a script that runs periodically (for example, through a scheduled task) and sends an email alert for any mailboxes that exceed 30 GB. Here's a basic example of what that script might look like:

      $largeMailboxes = Get-Mailbox -ResultSize Unlimited | Get-MailboxStatistics | Where-Object { $_.TotalItemSize.Value.ToGB() -gt 30 }
      if ($largeMailboxes) {
       $body = "The following mailboxes exceed 30 GB:`n"
       foreach ($mailbox in $largeMailboxes) {
           $body += "$($mailbox.DisplayName): $($mailbox.TotalItemSize)`n"
       }
       Send-MailMessage -To "******@yourdomain.com" -From "******@yourdomain.com" -Subject "Mailbox Size Alert" -Body $body -SmtpServer "your.smtp.server"
      }