diff --git a/src/Services/MessagingService.cs b/src/Services/MessagingService.cs
index 50976a3..fc13216 100644
--- a/src/Services/MessagingService.cs
+++ b/src/Services/MessagingService.cs
@@ -16,19 +16,17 @@ public class MessagingService
         this.ctx = ctx;
     }
 
-    public Model.Message AddMessageToViking(Viking viking, Viking? toViking, MessageType messageType, MessageTypeID messageTypeID, MessageLevel messageLevel, string data, string memberMessage = "", string nonMemberMessage = "", bool IsNew = true, bool IsDeleted = false, bool isReply = false, bool isPrivate = false, int parentMessageId = 0)
+    public Model.Message AddMessageToViking(Viking? viking, Viking toViking, MessageType messageType, MessageTypeID messageTypeID, MessageLevel messageLevel, string data, string memberMessage = "", string nonMemberMessage = "", bool IsNew = true, bool IsDeleted = false, bool isReply = false, bool isPrivate = false, int parentMessageId = 0)
     {
         // get execution UTC timestamp
         DateTime now = DateTime.UtcNow;
 
         // for generating ConversationId and QueueId
         Random rnd = new Random();
-        
+
         // construct message
         Model.Message message = new Model.Message
         {
-            Viking = viking,
-            VikingId = viking.Id,
             ToViking = toViking,
             ToVikingId = toViking.Id,
             QueueID = rnd.Next(1000, 9999),
@@ -46,6 +44,16 @@ public class MessagingService
             IsPrivate = isPrivate
         };
 
+        if (viking == null)
+        {
+            message.Viking = null;
+            message.VikingId = -1; // -1 = System Message
+        } else 
+        {
+            message.Viking = viking;
+            message.VikingId = viking.Id;
+        }
+
         if (isReply && parentMessageId > 0)
         {
             // get message this is in reply to
@@ -139,7 +147,7 @@ public class MessagingService
                     MessageID = message.Id,
                     ConversationID = message.ConversationID ?? 0,
                     ReplyToMessageID = message.ParentMessageId,
-                    Creator = msgAuthor.Uid.ToString() ?? "Ghost",
+                    Creator = msgAuthor.Uid.ToString() ?? new Guid().ToString(),
                     CreateTime = message.CreatedAt,
                     UpdateDate = message.LastUpdatedAt,
                     MessageType = message.MessageType.Value,
@@ -169,7 +177,7 @@ public class MessagingService
                     UserMessageQueueID = message.QueueID,
                     MessageID = message.Id,
                     MessageTypeID = (int?)message.MessageTypeID,
-                    FromUserID = msgAuthor.Uid.ToString() ?? "NotFound",
+                    FromUserID = msgAuthor.Uid.ToString() ?? new Guid().ToString(),
                     MemberMessage = message.MemberMessage ?? "NoData",
                     NonMemberMessage = message.NonMemberMessage ?? "NoData",
                     Data = data
@@ -182,7 +190,7 @@ public class MessagingService
                     UserMessageQueueID = message.QueueID,
                     MessageID = message.Id,
                     MessageTypeID = (int?)message.MessageTypeID,
-                    FromUserID = msgAuthor.Uid.ToString() ?? "NotFound",
+                    FromUserID = msgAuthor.Uid.ToString() ?? new Guid().ToString(),
                     MemberMessage = message.MemberMessage ?? "NoData",
                     NonMemberMessage = message.NonMemberMessage ?? "NoData",
                     Data = message.Data
@@ -205,7 +213,7 @@ public class MessagingService
                         MessageID = reply.Id,
                         ConversationID = reply.ConversationID ?? 0,
                         ReplyToMessageID = reply.ParentMessageId,
-                        Creator = replyAuthor.Uid.ToString() ?? "Ghost",
+                        Creator = replyAuthor.Uid.ToString() ?? new Guid().ToString(),
                         CreateTime = reply.CreatedAt,
                         UpdateDate = reply.LastUpdatedAt,
                         MessageType = reply.MessageType.Value,
@@ -252,13 +260,13 @@ public class MessagingService
             Viking? msgAuthor = ctx.Vikings.FirstOrDefault(e => e.Id == message.VikingId) ?? new Viking();
 
             if(message.IsDeleted) { ctx.Messages.Remove(message); continue; }
-            if(DateTime.Compare(now, message.CreatedAt.AddMinutes(30)) > 0)  { message.IsNew = false; continue; } // sometimes clients won't set IsNew flag when updating messages, so do not add messages more than 30 minutes old to response
+            if(DateTime.Compare(now, message.CreatedAt.AddMinutes(30)) > 0 && !showOldMessages)  { message.IsNew = false; continue; } // sometimes clients won't set IsNew flag when updating messages, so do not add messages more than 30 minutes old to response
             if(!message.IsNew && !showOldMessages) continue;
             messageInfos.Add(new MessageInfo
             {
                 MessageID = message.Id,
                 UserMessageQueueID = message.QueueID,
-                FromUserID = msgAuthor.Uid.ToString() ?? "NotFound",
+                FromUserID = msgAuthor.Uid.ToString() ?? new Guid().ToString(),
                 MessageTypeID = (int?)message.MessageTypeID,
                 Data = message.Data ?? "NoData",
                 MemberMessage = message.MemberMessage ?? "NoMessage",