Question

Just after running my Delphi application i check for the installed MS Outlook version because my app works differntly if in the machine there is a Outlook version greater than 2007.

I also wrote an Outlook Addin that sometimes crashes. I suspect
those crashes are related to the Outlook instances I create at startup.

Is there a way to create these ActiveX instances in a “softer way”. As i create the OLE object now I see in Tray Bar an icon whose hint says “Outlook is being used by another application”, may be if it were possible to remove this I would also see my problems disappear.

Somehow what I would like to achive is the same done here, where the wdDoNotSaveChanges parameter allows a “smoother” use of the OLE Object.

This is the code i use to check for Outlook version:

var
  OutlookApp: OLEVariant;
  Version : String;
begin
  { Create the OLE Object }
  Try
    OutlookApp := CreateOLEObject('Outlook.Application');
    Version := OutlookApp.version;
    OutlookVersion := StrToint(SubstrEx(1,Version,'.'));
    OutlookApp := VarNull;
  except
    on E: Exception do
    begin
      OutlookVersion := -1;
    end;
  End;

Answer 1

Your approach is different from the one suggested by Microsoft here:

How to: Check the Version of Outlook .

Their version uses the Microsoft Installer functionality to detect the location of the Outlook executable, then extract the file version straight from there. This approach doesn’t suffer from any of the problems you might encounter when instancing Outlook like you do. It is also a lot faster.

It does however suffer from one major disadvantage: it will only work if Outlook is deployed properly, the Microsoft way. On consumer machines this isn’t so much of a problem, but in enterprise environments you might (/will) occasionally run into stripped down custom installs by overzealous IT departments that do not include the necessary MSI footprint.

Depending on your target audience, that might not be a real problem at all.