Remove Spam/Phishing Email From All Mailboxes

In 365, you can use Compliance Searches to search and/or remove emails across all of your user’s mailboxes. Compliance searches have replaced the Search-Mailbox cmdlet, which has been deprecated as of April 2020.

Pre-Requisites

You must be a member of the Discovery Management role group or be assigned the Compliance Search management role. Here’s how you can add a user to the Discovery Management group and confirm membership

#Connect to Security and Compliance Center
$UserCredential = Get-Credential
$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.compliance.protection.outlook.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection
Import-PSSession $Session -DisableNameChecking

#Add User to Discovery Management Group (Replace John Doe with your user)
Add-RoleGroupMember -Identity "Discovery Management" -Member "John Doe"

#Confirm Membership
Get-RoleGroupMember -Identity "Discovery Management"

#Disconnect Session
Remove-PSSession $Session

Function to Search & Remove Spam/Phishing Emails From All Mailboxes

Modify the Search Variables below to suite your needs

Function RemoveMaliciousEmails()
{
	#MODIFY THE BELOW VARIABLES - YOU MUST USE THEM ALL AND OPTIONALLY LEAVE SUBJECT BLANK!!!
	$compSearchName = "MaliciousEmail_$(Get-Date -Format "MMddyyyy_HHmm")"
	$compStartDate = "2020-02-24"  #YYYY-MM-DD
	$compEndDate = "2020-02-25"	   #Must be different than Start Date, if searching "today" make this date tomorrow
	$compFrom = "hacker@phishing.com" #You can use just the domain for a wildcard sender BUT USE WITH CAUTION
	$compSubject = "Phishing Test"  #Use backtick ` to escape special characters in the subject such as a quote ex: Dave shared `"New File`" with you
	#
	#DO NOT MODIFY ANYTHING BELOW HERE
	$UserCredential = Get-Credential
	$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.compliance.protection.outlook.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection
	Import-PSSession $Session -DisableNameChecking
	Write-Host "NAME: $($compSearchName)"
	Write-Host "START: $($compStartDate)"
	Write-Host "END: $($compEndDate)"
	Write-Host "FROM: $($compFrom)"
	Write-Host "SUBJECT: $($compSubject)"
	If ($compSubject.Trim() -eq "")
	{
		$ncs = New-ComplianceSearch -Name $compSearchName -ExchangeLocation all -ContentMatchQuery "(c:c)(received=$compStartDate..$compEndDate)(from=$compFrom)"
	}
	Else
	{
		$ncs = New-ComplianceSearch -Name $compSearchName -ExchangeLocation all -ContentMatchQuery "(c:c)(received=$compStartDate..$compEndDate)(from=$compFrom)(subject=`"$compSubject`")"
	}	
	Write-Host "[$(Get-Date -Format G)] Start Compliance Search: $($compSearchName)"
	Write-Host -NoNewLine "[$(Get-Date -Format G)] Searching"
	Start-ComplianceSearch -Identity $compSearchName
	$resultSearch = Get-ComplianceSearch -Identity $compSearchName
	While ($resultSearch.Status -ne "Completed")
	{
		$resultSearch = Get-ComplianceSearch -Identity $compSearchName
		Write-Host -NoNewLine "."
		Start-Sleep -s 5
	}
	If (($resultSearch.Items -le 0) -OR ([string]::IsNullOrWhiteSpace($resultSearch.SuccessResults)))
	{
		Write-Host "`n[$(Get-Date -Format G)] Search completed with 0 successful results, Invalid Search Quitting!" -ForegroundColor Red
		Remove-PSSession $Session
		Return
	}
	Elseif ($resultSearch.Items -ge 500)
	{
		Write-Host "`n[$(Get-Date -Format G)] Search Completed with $($resultSearch.Items) successful results, you will need to run mulitple times!" -ForegroundColor Yellow
	}
	Else 
	{
		Write-Host "`n[$(Get-Date -Format G)] Search Completed with $($resultSearch.Items) successful results"
	}
	Write-Host "[$(Get-Date -Format G)] Create Preview and Export of Results"
	Write-Host -NoNewLine "[$(Get-Date -Format G)] Processing"
	$ncsa = New-ComplianceSearchAction -SearchName $compSearchName -Preview
	$resultPreview = Get-ComplianceSearchAction -Identity "$($compSearchName)_Preview"
	$ncsa = New-ComplianceSearchAction -SearchName $compSearchName -Export -ExchangeArchiveFormat SinglePst -Format FxStream
	$resultExport = Get-ComplianceSearchAction -Identity "$($compSearchName)_Export"
	While ($resultPreview.Status -ne "Completed" -AND $resultExport.Status -ne "Completed")
	{
		$resultPreview = Get-ComplianceSearchAction -Identity "$($compSearchName)_Preview"
		$resultExport = Get-ComplianceSearchAction -Identity "$($compSearchName)_Export"
		#Write-Host "[$(Get-Date -Format G)] Processing..."
		Write-Host -NoNewLine "."
		Start-Sleep -s 5
	}
	Write-Host "`n[$(Get-Date -Format G)] Preview and Export successfully created"
	Write-Host "[$(Get-Date -Format G)] View Results at https://protection.office.com/" 
	Write-Host "[$(Get-Date -Format G)] Preview: Search -> Content Search -> Searches tab -> $($compSearchName)"
	Write-Host "[$(Get-Date -Format G)] Export:  Search -> Content Search -> Exports tab -> $($compSearchName)_Export"
	Write-Host "[$(Get-Date -Format G)] Start Purging emails"
	Write-Host -NoNewLine "[$(Get-Date -Format G)] Purging"
	$ncsa = New-ComplianceSearchAction -SearchName $compSearchName -Purge -PurgeType HardDelete -Confirm:$False
	$resultPurge = Get-ComplianceSearchAction -Identity "$($compSearchName)_Purge"
	While ($resultPurge.Status -ne "Completed")
	{
		$resultPurge = Get-ComplianceSearchAction -Identity "$($compSearchName)_Purge"
		Write-Host -NoNewLine "."
		Start-Sleep -s 5
	}
	Write-Host "`n[$(Get-Date -Format G)] Purge complete"
	$confirmDelete = Read-Host "Delete Compliance Search, Preview, Export, and Purge? [Y/N]"
	If ($confirmDelete -eq 'Y') 
	{
		Write-Host "[$(Get-Date -Format G)] Deleting Compliance Search, Preview, Export, and Purge..."
		Remove-ComplianceSearchAction -Identity "$($compSearchName)_Preview" -Confirm:$False
		Remove-ComplianceSearchAction -Identity "$($compSearchName)_Export" -Confirm:$False
		Remove-ComplianceSearchAction -Identity "$($compSearchName)_Purge" -Confirm:$False
		Remove-ComplianceSearch -Identity $compSearchName -Confirm:$False
	}
	Write-Host "[$(Get-Date -Format G)] Removing Powershell Session..."
	Remove-PSSession $Session
}
RemoveMaliciousEmails