This message is shown on startup on Outlook 2013 for an Outlook AddIn developed using .Net 3.5. I have tried the suggestions in this post: This addin caused outlook to start slowly But without any luck. This is my initial method:
private void ThisAddIn_Startup(object sender, System.EventArgs e)
{
_Explorers = this.Application.Explorers;
_Inspectors = this.Application.Inspectors;
_Explorers.Application.NewMailEx += new Outlook.ApplicationEvents_11_NewMailExEventHandler(Application_ItemReceive);
_Explorers.Application.Reminders.ReminderFire += new Outlook.ReminderCollectionEvents_ReminderFireEventHandler(Application_ReminderFire);
outlookNamespace = this.Application.GetNamespace("MAPI");
}