Sequential process Outlook rules - vba

Question

I use a outlook rule to process incoming mail via a VBA macro.
in the vba various actions are triggerd to process attachments of the incoming mail.
The problem is, there somethimes is a stack of e-mails that need to be processed.
I cant seem to find a way how to trigger the one by one.
I want to wait a few seconds before processing the next mail, if there is a stack.
Putting a sleep method in the macro doesnt seem to have effect. the rule doesnt seem to wait for the previous message to be done.
My method i something like:
Is there a way to accomplish this behaviour?
Private Sub ProcessMail(ByVal Item As Object)
Dim objNS As Outlook.NameSpace
Set objNS = GetNamespace("MAPI")
If TypeOf Item Is Outlook.MailItem Then
Dim Msg As Outlook.MailItem
DoProcessingMethod
End If
End If
End Sub
Putting a wait or sleep in the method doesnt cause it to be processed one by one.

Answer 1

GD Arnold,
You could indeed use the ItemAdd option as per #Brett's answer.
I use a similar process to automatically upload received data (as attachment in an email) and upload this to a MySQL database. The action is triggered by the ItemAdd method and mails are checked one-by-one.
Simplified instructions:
Add a Class to your VBA code named "EventClassModule"
In your class, type
Public WithEvents dItems As Outlook.Items
In your ThisOutlookSession make a sub that registers the event_handler:
Sub Register_Event_Handler()
Set myClass.dItems = Outlook.Items
End Sub
In your ThisOutlookSession make a sub that handles the ItemAdd event as below:
Private Sub dItems_ItemAdd(ByVal newItem As Object)
On Error GoTo ErrorHandler
Dim msg As Outlook.MailItem
If newItem.Class = olMail Then
Set msg = newItem
'Do something with the msg item, check rules, check subject, check whatever
'This will process messages when the arrive in your mailbox one by one.
End If
ProgramExit:
Exit Sub
ErrorHandler:
MsgBox Err.Number & " - " & Err.Description
Resume ProgramExit
End Sub
These steps should provide you with a sub that is triggered when a new mail arrives.
You could then call a function/sub like below.
The below sub runs all rules based on an optional ruleSet variable, it checks the rule.Name against the ruleSet and if the ruleSet string exists in the rule.Name then it executes some code. This way you can have multiple rules and only execute some of them based on which 'ruleSet' they are part of. You can define that by altering their name.
It's a refinement of the 'Run Rules' option in Outlook.
Some of this code came frome here: Setting VBA to read personal inbox
Sub runRules(Optional ruleSet As String)
Dim olStore As Outlook.Store
Dim myRules As Outlook.Rules
Dim tmpInbox As Outlook.Folder
Dim tmpSent As Outlook.Folder
Dim rl As Outlook.Rule
'On Error Resume Next
'toTmpBox (ruleSet)
' get default store (where rules live)
Set olStore = Application.Session.DefaultStore
With olStore
Set tmpInbox = .GetDefaultFolder(olFolderInbox) '.Folders("tmpInbox")
Set tmpSent = .GetDefaultFolder(olFolderSentMail) '.Folders("tmpSentBox")
End With
' get rules
Set myRules = olStore.GetRules
' iterate through all the rules
For Each rl In myRules
Debug.Print rl.Conditions.Body.Enabled & " " & rl.Conditions.Body.Text
If InStr(LCase(rl.Name), ruleSet) > 0 And (rl.Enabled) Then
rl.Execute ShowProgress:=True, Folder:=tmpInbox
If ruleSet = "autorun" Then
rl.Execute ShowProgress:=True, Folder:=olStore.GetDefaultFolder(olFolderSentMail)
End If
ruleList = ruleList & vbCrLf & rl.Name
End If
Next
' tell the user what you did
ruleList = "These rules were executed " & _
vbCrLf & ruleList
MsgBox ruleList, vbInformation, "Macro: RunMyRules"
CleanUp:
Set olStore = Nothing
Set tmpInbox = Nothing
Set tmpSent = Nothing
Set rl = Nothing
Set myRules = Nothing
End Sub

Answer 2

I have come across a similar problem. In my case my tool would run at regular time interval and each time I had to capture new emails only. Now new emails could be one or multiple. the solution I found was as given below.
Each time the tool would run. it will capture the new emails and just mark a simple ',' or '|' anything of your choice at the end of the subject in such a way that no one will notice. Now next time when the tool runs it checks if the emails received for the entire day or two (based on your requirements) has those markers or not.
This solution works if the email communication is one way. If we use these email for chain emails then their is another solution.
Here you will have to save the time max time of emails captured in the last run. Now each time you run you just have to run it for the entire day and put an if statement that is should be greater then time last captured.
Now to store the max time you might need to create a folder and an email. The email can help you to store the each time the run happens
item.subject = maxtime
item.save