Send-EWSEmail.ps1

<#
    Send Exchange Web Services Email
    Author: Steve Borosh (@rvrsh3ll)
    License: BSD 3-Clause
    Required Dependencies: Exchange Web Services (EWS) Managed API dll from https://www.microsoft.com/en-us/download/details.aspx?id=42951
    Optional Dependencies: None
#>
function Send-EWSEmail {
<#
    .DESCRIPTION
        Send an email using EWS
    
    .EXAMPLE
        Import-Module -Name 'C:\Program Files\Microsoft\Exchange\Web Services\2.2\Microsoft.Exchange.WebServices.dll'
        Import-Module .\Send-EWSEmail.ps1
        Send-EWSEmail -ServiceURL "https://outlook.office365.com/EWS/Exchange.asmx" -Recipient "me@me.com" -Subject "Important Message!" -EmailBody "All, <br> Check out the attachment." -Attachment .\WordDocument.rtf
#>
    [CmdletBinding()]
    Param(
        [Parameter(Mandatory = $True)]
        [String]
        $ServiceURL,

        [Parameter(Mandatory = $True)]
        [String]
        $Recipient,

        [Parameter(Mandatory = $True)]
        [String]
        $Subject,

        [Parameter(Mandatory = $False)]
        [String]
        $EmailBody,

        [Parameter(Mandatory = $False)]
        [String]
        $Attachment
    )
    BEGIN {
        $EXCHService = New-Object -TypeName Microsoft.Exchange.WebServices.Data.ExchangeService
        $Credential = Get-Credential
    }
    
    PROCESS {
        Write-Output "Sending...."
        $EXCHService.Credentials = New-Object -TypeName Microsoft.Exchange.WebServices.Data.WebCredentials -ArgumentList $Credential.UserName, $Credential.GetNetworkCredential().Password
        $EXCHService.AutodiscoverUrl($Credential.UserName, {$true})
        $EXCHService.Url = $ServiceURL
        $eMail = New-Object -TypeName Microsoft.Exchange.WebServices.Data.EmailMessage -ArgumentList $EXCHService
        $eMail.Subject = $Subject
        $eMail.Body = $EmailBody
        $eMail.ToRecipients.Add($Recipient) | Out-Null
        if ($Attachment) {
            $email.Attachments.AddFileAttachment($Attachment) | Out-Null
        }
        $eMail.Send()
    }

    END {
        Write-Output "Finished"
    }   
}