Adding attachment >3 MB not possible if no client secret is used

[scriptkiddy666]

Adding attachment >3 MB not possible if no client secret is used

[PrzemyslawKlys]

Try using PS 7, it should provide better error reporting. Also do you have proper rights to upload files? As ReadWrite Emails? Send is not enough.

[scriptkiddy666]

Same with PS7 (do I have to "reinstall" the module for PS7?):

Yes, both, my managed identity and the app registration have Mail.Send and Mail.ReadWrite. (That should be fine, because it worked with the client secret for the same app registration.)

[PrzemyslawKlys]

You don't have to reinstall module.

Just to clarify:

• Does it work for 4MB plus with Connect-MgGraph and MgGraphRequest with ClientSecret?
• It doesn't work with Connect-MgGraph and MgGraphRequest with Certificate?

[PrzemyslawKlys]

And I assume in all cases the mailbox does exists? The one you're sending it with?

[scriptkiddy666]

You don't have to reinstall module.

Just to clarify:

• Does it work for 4MB plus with Connect-MgGraph and MgGraphRequest with ClientSecret?
  Yes. I just tried it again (also without executing Connect-MgGraph before) by just adding the -Credential parameter with the ClientSecret. Works like a charm. (The parameter -MgGraphRequeset was not added.)

• It doesn't work with Connect-MgGraph and MgGraphRequest with Certificate?
  Yes. I used Connect-MgGraph with my certificate before executing Send-EmailMessage.
  (-Credential parameter of Send-EmailMessage removed and -MgGraphRequest added instead.)

And I assume in all cases the mailbox does exists? The one you're sending it with?

Correct. (It's the always the same mailbox and I also tried it with a different one, but the error is the same.)

[scriptkiddy666]

I'm now using the following workaround without the need for a client secret:

$null = Connect-AzAccount -Identity
[System.Object]$AccessToken = (Get-AzAccessToken -ResourceTypeName 'MSGraph' -AsSecureString -WarningAction 'SilentlyContinue').Token
[System.Object]$Credentials = ConvertTo-GraphCredential -MsalToken ([System.Net.NetworkCredential]::new('', $AccessToken).Password)
[System.String[]]$Attachments = @(XXX)

Send-EmailMessage -From 'XXX' -To 'XXX' -HTML "XXX" -Subject 'XXX' -Graph -ReplyTo "XXX" -Credential $Credentials -Attachment $Attachments -DoNotSaveToSentItems