Exchange Backup Fails With: "Failed to get folder properties. Not allowed to access Non IPM folder"

$configFilePath = "C:\ProgramData\Veeam\Backup365\Config.xml"
$xmlContent = [xml](Get-Content $configFilePath)
if ($xmlContent.SelectSingleNode("//Archiver/Proxy[@SkipTeamsMessagesDataFolders='True']")) {
    Write-Output "SkipTeamsMessagesDataFolders setting already exists. No changes made."
} else {
    Copy-Item -Path $configFilePath -Destination "$configFilePath$($(Get-Date -Format '.yyyyMMdd')).old"
    $newElement = $xmlContent.CreateElement("Proxy")
    $newElement.SetAttribute("SkipTeamsMessagesDataFolders", "True")
    $archiverNode = $xmlContent.SelectSingleNode("//Archiver")
    $archiverNode.AppendChild($newElement)
    $xmlContent.Save($configFilePath)
    Write-Output "SkipTeamsMessagesDataFolders setting added."
    Restart-Service -Name "Veeam.Archiver.Service"
}