Grabbing EML files from drop folder before job-email-delivery gets them

Often when troubleshooting incoming email problems in SharePoint, we would temporarily disable the Microsoft SharePoint Foundation Incoming E-Mail (job-email-delivery) timer job, then send an email and watch the folder for an EML file to show up.

Alternatively, you can register a FileSystemWatcher to listen on a Created event. Then, this code can copy out the EML file to some safe place before job-email-delivery gets it.

To install the listener:

$destination = 'c:\Windows\Temp\maillogs' # Make sure your powershell user can write here
$dropFolder = 'C:\inetpub\mailroot\Drop' # Drop folder as configured in SharePoint

$filter = '*.eml'

$fsw = New-Object System.IO.FileSystemWatcher($dropFolder, $filter)
$fsw.IncludeSubdirectories = $false
$fsw.NotifyFilter = [System.IO.NotifyFilters]'FileName,LastWrite' # seems to need this to avoid some IOExceptions

$onCreated = Register-ObjectEvent -InputObject $fsw -EventName Created -Action {
  Write-Host "$($Event.TimeGenerated) : Incoming email file - $($Event.SourceEventArgs.Name)"
  Copy-Item $Event.SourceEventArgs.FullPath -Destination $destination -Force -Verbose
}

To remove the listener:

Unregister-Event -SourceIdentifier $onCreated.Name
$onCreated.Dispose()

Unknowns:

• Does not account for large incoming files that are temporarily locked while being copied
• Not sure if this causes problems if job-email-delivery tries to access (or even remove) file while Copy-Item is being called.
• Not sure if this is guaranteed to happen before job-email-delivery
• Not sure of the performance impact

Automatically capturing matching Failed Request Trace Logs

I was trying to troubleshoot a particularly challenging user identity issue with SharePoint and thought about using Failed Request Tracing which I will write about some other time.

While doing so, I wanted a way to grab the relevant fr*.xml files. I thought that it would streamline things if I could watch for these log files as they are created, run some filter against them and, if matched, copy the file to another folder (hopefully before the log rolls over).

Then I came across this post regarding "check folder for new files": https://social.technet.microsoft.com/Forums/scriptcenter/en-US/c75c7bbd-4e32-428a-b3dc-815d5c42fd36/powershell-check-folder-for-new-files
I adapted it to my purpose:

$destination = 'c:\Inetpub\Logs\FailedReqLogFiles\Temp'
$folder = 'C:\Inetpub\logs\FailedReqLogFiles\W3SVC2'

$filter = 'fr*.xml'
$fsw = New-Object IO.FileSystemWatcher $folder, $filter -Property @{
  IncludeSubdirectories = $false
  NotifyFilter = [IO.NotifyFilters]'FileName, LastWrite'
}

$onCreated = Register-ObjectEvent $fsw Created -SourceIdentifier FileCreated -Action {
  $path = $Event.SourceEventArgs.FullPath
  $name = $Event.SourceEventArgs.Name
  $changeType = $Event.SourceEventArgs.ChangeType
  $timeStamp = $Event.TimeGenerated
  $frlogfile = Get-Content $path
  $xml = [xml]$frlogfile
  $url = $xml.failedRequest.url
  Write-Host "The file $($name) was $($changeType) at $($timeStamp) with URL $($url)"
  if (***my matching conditions***) {
    Copy-Item $path -Destination $destination -Force -Verbose
  }
}

I definitely need to read up more on Get-Event, Get-EventSubscriber, Register-*Event cmdlets as well as the IO.FileSystemWatcher class. I think I could do some pretty cool stuff with them.