BUG-2743: Cleanup of MAPI & Outlook logic, removed the check on "HKEY_LOCAL_MACHINE\SOFTWARE(\WOW6432Node)\Microsoft\Windows Messaging Subsystem" with the MAPI value in favor of the HKEY_LOCAL_MACHINE\SOFTWARE(\WOW6432Node)\Clients\Mail where the default value contains the name, this should hopefully solve some issues.

Greenshot/Destinations/EmailDestination.cs

@@ -26,6 +26,7 @@ using Greenshot.Configuration;
 using Greenshot.Helpers;
 using GreenshotPlugin.Core;
 using GreenshotPlugin.Interfaces;
+using Microsoft.Win32;
 
 namespace Greenshot.Destinations {
 	/// <summary>
@@ -39,12 +40,9 @@ namespace Greenshot.Destinations {
 
 		static EmailDestination() {
 			// Logic to decide what email implementation we use
-            if (!EmailConfigHelper.HasMapi()) return;
-
-            _isActiveFlag = false;
-            _mapiClient = EmailConfigHelper.GetMapiClient();
+			_mapiClient = RegistryHive.LocalMachine.ReadKey64Or32(@"Clients\Mail");
             if (!string.IsNullOrEmpty(_mapiClient)) {
-                // Active as we have a mapi client, can be disabled later
+                // Active as we have a MAPI client, can be disabled later
                 _isActiveFlag = true;
             }
         }
@@ -66,11 +64,9 @@ namespace Greenshot.Destinations {
 				if (_isActiveFlag) {
 					// Disable if the office plugin is installed and the client is outlook
 					// TODO: Change this! It always creates an exception, as the plugin has not been loaded the type is not there :(
-					Type outlookdestination = Type.GetType("GreenshotOfficePlugin.OutlookDestination,GreenshotOfficePlugin");
-					if (outlookdestination != null) {
-						if (_mapiClient.ToLower().Contains("microsoft outlook")) {
-							_isActiveFlag = false;
-						}
+					var outlookDestination = Type.GetType("GreenshotOfficePlugin.OutlookDestination,GreenshotOfficePlugin", false);
+					if (outlookDestination != null && _mapiClient.ToLower().Contains("microsoft outlook")) {
+						_isActiveFlag = false;
 					}
 				}
 				return base.IsActive && _isActiveFlag;

Greenshot/Helpers/MailHelper.cs

@@ -80,15 +80,7 @@ namespace Greenshot.Helpers {
 			
 			// Store the list of currently active windows, so we can make sure we show the email window later!
 			var windowsBefore = WindowDetails.GetVisibleWindows();
-			//bool isEmailSend = false;
-			//if (EmailConfigHelper.HasOutlook() && (CoreConfig.OutputEMailFormat == EmailFormat.OUTLOOK_HTML || CoreConfig.OutputEMailFormat == EmailFormat.OUTLOOK_TXT)) {
-			//	isEmailSend = OutlookExporter.ExportToOutlook(tmpFile, captureDetails);
-			//}
-			if (/*!isEmailSend &&*/ EmailConfigHelper.HasMapi()) {
-				// Fallback to MAPI
-				// Send the email
-				SendImage(tmpFile, captureDetails.Title);
-			}
+			SendImage(tmpFile, captureDetails.Title);
 			WindowDetails.ActiveNewerWindows(windowsBefore);
 		}
 

GreenshotOfficePlugin/Destinations/OutlookDestination.cs

@@ -30,6 +30,7 @@ using GreenshotPlugin.IniFile;
 using GreenshotPlugin.Interfaces;
 using GreenshotPlugin.Interfaces.Plugin;
 using Microsoft.Office.Interop.Outlook;
+using Microsoft.Win32;
 
 namespace GreenshotOfficePlugin.Destinations {
 	/// <summary>
@@ -47,23 +48,40 @@ namespace GreenshotOfficePlugin.Destinations {
 		private const string MapiClient = "Microsoft Outlook";
 		private readonly string _outlookInspectorCaption;
 		private readonly OlObjectClass _outlookInspectorType;
-		private readonly OutlookEmailExporter _outlookEmailExporter = new OutlookEmailExporter();
+		private readonly OutlookEmailExporter _outlookEmailExporter = new();
 
 		static OutlookDestination() {
-			if (EmailConfigHelper.HasOutlook()) {
+			if (HasOutlook()) {
 				IsActiveFlag = true;
 			}
 			ExePath = PluginUtils.GetExePath("OUTLOOK.EXE");
 			if (ExePath != null && File.Exists(ExePath)) {
 				WindowDetails.AddProcessToExcludeFromFreeze("outlook");
 			} else {
-				ExePath = null;
+				ExePath = GetOutlookExePath();
 			}
 			if (ExePath == null) {
 				IsActiveFlag = false;
 			}
 		}
 
+
+		private static string GetOutlookExePath() => RegistryHive.LocalMachine.ReadKey64Or32(@"Microsoft\Windows\CurrentVersion\App Paths\OUTLOOK.EXE");
+
+		/// <summary>
+		/// Check if Outlook is installed
+		/// </summary>
+		/// <returns>Returns true if outlook is installed</returns>
+		private static bool HasOutlook()
+		{
+			string outlookPath = GetOutlookExePath();
+			if (outlookPath == null)
+			{
+				return false;
+			}
+			return File.Exists(outlookPath);
+		}
+
 		public OutlookDestination() {
 		}
 

GreenshotPlugin/Core/EmailConfigHelper.cs

@@ -1,54 +0,0 @@
-/*
- * Greenshot - a free and open source screenshot tool
- * Copyright (C) 2007-2021 Thomas Braun, Jens Klingen, Robin Krom
- * 
- * For more information see: http://getgreenshot.org/
- * The Greenshot project is hosted on GitHub https://github.com/greenshot/greenshot
- * 
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 1 of the License, or
- * (at your option) any later version.
- * 
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- * 
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-using System.IO;
-using Microsoft.Win32;
-
-namespace GreenshotPlugin.Core {
-	/// <summary>
-	/// Description of EmailConfigHelper.
-	/// </summary>
-	public static class EmailConfigHelper {
-
-		public static string GetMapiClient() => RegistryHive.LocalMachine.ReadKey64Or32(@"Clients\Mail");
-		
-		public static bool HasMapi()
-		{
-			var value = RegistryHive.LocalMachine.ReadKey64Or32(@"Microsoft\Windows Messaging Subsystem", "MAPI", "0");
-			return "1".Equals(value);
-		}
-		
-		public static string GetOutlookExePath() => RegistryHive.LocalMachine.ReadKey64Or32(@"Microsoft\Windows\CurrentVersion\App Paths\OUTLOOK.EXE");
-
-		/// <summary>
-		/// Check if Outlook is installed
-		/// </summary>
-		/// <returns>Returns true if outlook is installed</returns>
-		public static bool HasOutlook() {
-			string outlookPath = GetOutlookExePath();
-			if (outlookPath == null)
-			{
-				return false;
-			}
-			return File.Exists(outlookPath);
-		}
-	}
-}