$ConnectParams = @{
ClientId = 'xxxxx'
TenantId = 'xxxxx'
CertificateThumbprint = 'xxxxx'
}
Connect-Graph @ConnectParams

Function ConvertTo-IMicrosoftGraphRecipient {
[cmdletbinding()]
Param(
[array]$smtpAddresses
)
foreach ($address in $smtpAddresses) {
@{
emailAddress = @{address = $address}
}
}
}

Function ConvertTo-IMicrosoftGraphAttachment {
[cmdletbinding()]
Param(
[string[]]$UploadDirectory
)
foreach ($fl in $UploadDirectory) {
if ($fl) { }
else { $fl = "un" }
$fpath = "C:\inetpub\wwwroot\flags\PNG\$fl.png"
$encodedAttachment = [convert]::ToBase64String((Get-Content $fpath -Encoding byte))
@{
"@odata.type"= "#microsoft.graph.fileAttachment"
name = $fl
contentBytes = $encodedAttachment
contentID = $fl
contentType = "image/png"
}
}
}

$arFlags = @()
foreach ($lc in $logCollection)
{
$f_flag = $lc.flag

if ($f_flag -eq "") { $f_flag = "un" }
write-host "flag $f_flag"
if ($flaglist -notcontains $f_flag) { $arFlags += $f_flag }

$null = $flaglist.add("$f_flag")
}
$arflags

$attachments = ConvertTo-IMicrosoftGraphAttachment -UploadDirectory $arflags

$emailRecipients = @(
'user@domain.com'
)

$toRecipients = ConvertTo-IMicrosoftGraphRecipient -SmtpAddresses $emailRecipients

$addimg = "cid" + ":" + "ie"

$contentMG += "<table><th>Flag></th></tr>"
foreach ($lc in $logCollection)
{
$l_flag = $lc.flag
$l_location = $lc.location
$contentMG += "<tr><td><img src=cid`:$l_flag></td></tr>"
}

$body = @{
content = $contentMG
ContentType = 'html'
}

#Create Message (goes to drafts)
$Message = New-MgUserMessage -UserId user@domain.com -Body $body -ToRecipients $toRecipients -Subject "Subject" -Attachments $Attachments

#Send Message
Send-MgUserMessage -UserId user@domain.com -MessageId $Message.Id