diff --git a/src/Umbraco.Core/Models/Identity/IIdentityUserLogin.cs b/src/Umbraco.Core/Models/Identity/IIdentityUserLogin.cs
index 276f601771..5e5f2c27f7 100644
--- a/src/Umbraco.Core/Models/Identity/IIdentityUserLogin.cs
+++ b/src/Umbraco.Core/Models/Identity/IIdentityUserLogin.cs
@@ -6,19 +6,16 @@ namespace Umbraco.Core.Models.Identity
     {
         /// <summary>
         /// The login provider for the login (i.e. Facebook, Google)
-        ///
         /// </summary>
         string LoginProvider { get; set; }
 
         /// <summary>
         /// Key representing the login for the provider
-        ///
         /// </summary>
         string ProviderKey { get; set; }
 
         /// <summary>
         /// User Id for the user who owns this login
-        ///
         /// </summary>
         int UserId { get; set; }
     }
diff --git a/src/Umbraco.Web/Editors/UsersController.cs b/src/Umbraco.Web/Editors/UsersController.cs
index 71e0dcf4a9..0d2af2118a 100644
--- a/src/Umbraco.Web/Editors/UsersController.cs
+++ b/src/Umbraco.Web/Editors/UsersController.cs
@@ -361,38 +361,8 @@ namespace Umbraco.Web.Editors
             user = CheckUniqueEmail(userSave.Email, u => u.LastLoginDate != default || u.EmailConfirmedDate.HasValue);
 
             var userMgr = TryGetOwinContext().Result.GetBackOfficeUserManager();
-            var inviteArgs = new UserInviteEventArgs(
-                Request.TryGetHttpContext().Result.GetCurrentRequestIpAddress(),
-                performingUser: Security.GetUserId().Result,
-                userSave);
-            userMgr.RaiseSendingUserInvite(inviteArgs);
-
-            // If the event is handled then return the data
-            if (inviteArgs.InviteHandled)
-            {
-                // if no local user was created then map the args manually for the UI
-                if (inviteArgs.User == null)
-                {
-                    return new UserDisplay
-                    {
-                        Name = userSave.Name,
-                        Email = userSave.Email,
-                        Username = userSave.Username
-                    };
-                }
-                else
-                {
-                    //map the save info over onto the user
-                    user = Mapper.Map(userSave, user);
-                    //ensure the invited date is set
-                    user.InvitedDate = DateTime.Now;
-                    //Save the updated user
-                    Services.UserService.Save(user);
-                    return Mapper.Map<UserDisplay>(user);
-                }
-            }
-
-            if (EmailSender.CanSendRequiredEmail == false)
+            
+            if (!EmailSender.CanSendRequiredEmail && !userMgr.HasSendingUserInviteEventHandler)
             {
                 throw new HttpResponseException(
                     Request.CreateNotificationValidationErrorResponse("No Email server is configured"));
@@ -430,16 +400,48 @@ namespace Umbraco.Web.Editors
             //ensure the invited date is set
             user.InvitedDate = DateTime.Now;
 
-            //Save the updated user
+            //Save the updated user (which will process the user groups too)
             Services.UserService.Save(user);
             var display = Mapper.Map<UserDisplay>(user);
 
-            //send the email
+            var inviteArgs = new UserInviteEventArgs(
+                Request.TryGetHttpContext().Result.GetCurrentRequestIpAddress(),
+                performingUser: Security.GetUserId().Result,
+                userSave,
+                user);
 
-            await SendUserInviteEmailAsync(display, Security.CurrentUser.Name, Security.CurrentUser.Email, user, userSave.Message);
+            try
+            {
+                userMgr.RaiseSendingUserInvite(inviteArgs);
+            }
+            catch (Exception ex)
+            {
+                Logger.Error<UsersController>(ex, "An error occured in a custom event handler while inviting the user");
+                throw new HttpResponseException(
+                    Request.CreateNotificationValidationErrorResponse($"An error occured inviting the user (check logs for more info): {ex.Message}"));
+            }
+
+            // If the event is handled then no need to send the email
+            if (inviteArgs.InviteHandled)
+            {
+                // if no user result was created then map the minimum args manually for the UI
+                if (!inviteArgs.ShowUserResult)
+                {
+                    display = new UserDisplay
+                    {
+                        Name = userSave.Name,
+                        Email = userSave.Email,
+                        Username = userSave.Username
+                    };
+                }                
+            }
+            else
+            {
+                //send the email
+                await SendUserInviteEmailAsync(display, Security.CurrentUser.Name, Security.CurrentUser.Email, user, userSave.Message);                
+            }
 
             display.AddSuccessNotification(Services.TextService.Localize("speechBubbles/resendInviteHeader"), Services.TextService.Localize("speechBubbles/resendInviteSuccess", new[] { user.Name }));
-
             return display;
         }
 
diff --git a/src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs b/src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs
index 7564b670cb..7266e688c5 100644
--- a/src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs
+++ b/src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs
@@ -78,7 +78,7 @@ namespace Umbraco.Web
             {
                 foreach (var error in externalLoginErrors.Errors)
                 {
-                    sb.AppendFormat(@"errors.push(""{0}"");", error).AppendLine();
+                    sb.AppendFormat(@"errors.push(""{0}"");", error.ToSingleLine()).AppendLine();
                 }
             }
 
diff --git a/src/Umbraco.Web/Security/BackOfficeUserManager.cs b/src/Umbraco.Web/Security/BackOfficeUserManager.cs
index b0e7125195..f91c128cde 100644
--- a/src/Umbraco.Web/Security/BackOfficeUserManager.cs
+++ b/src/Umbraco.Web/Security/BackOfficeUserManager.cs
@@ -634,6 +634,7 @@ namespace Umbraco.Web.Security
         }
 
         internal void RaiseSendingUserInvite(UserInviteEventArgs args) => OnSendingUserInvite(args);
+        internal bool HasSendingUserInviteEventHandler => SendingUserInvite != null;
 
         // TODO: Not sure why these are not strongly typed events?? They should be in netcore!
         public static event EventHandler AccountLocked;
diff --git a/src/Umbraco.Web/Security/UserInviteEventArgs.cs b/src/Umbraco.Web/Security/UserInviteEventArgs.cs
index 2cd0994c3c..9fb53a44c0 100644
--- a/src/Umbraco.Web/Security/UserInviteEventArgs.cs
+++ b/src/Umbraco.Web/Security/UserInviteEventArgs.cs
@@ -5,12 +5,16 @@ namespace Umbraco.Web.Security
 {
     public class UserInviteEventArgs : IdentityAuditEventArgs
     {
-        public UserInviteEventArgs(string ipAddress, int performingUser, UserInvite invitedUser, string comment = null)
+        public UserInviteEventArgs(string ipAddress, int performingUser, UserInvite invitedUser, IUser localUser, string comment = null)
             : base(AuditEvent.SendingUserInvite, ipAddress, comment, performingUser)
         {
             InvitedUser = invitedUser ?? throw new System.ArgumentNullException(nameof(invitedUser));
+            User = localUser;
         }
 
+        /// <summary>
+        /// The model used to invite the user
+        /// </summary>
         public UserInvite InvitedUser { get; }
 
         /// <summary>
@@ -19,12 +23,14 @@ namespace Umbraco.Web.Security
         public bool InviteHandled { get; set; }
 
         /// <summary>
-        /// If the event handler has created a local user then this is the result which is used to return the details to the UI
+        /// The local user that has been created that is pending the invite
+        /// </summary>        
+        public IUser User { get; }
+
+        /// <summary>
+        /// if set to true will show the edit user button in the UI, else it will not be shown
         /// </summary>
-        /// <remarks>
-        /// It is optional to create a local user in this event. In many cases the custom invite flow will be for external logins and then local users will
-        /// be created via the auto-linking process.
-        /// </remarks>
-        public IUser User { get; set; }        
+        public bool ShowUserResult { get; set; }
+
     }
 }