diff --git a/CHANGELOG.TXT b/CHANGELOG.TXT
index b912cad8..affb067c 100644
--- a/CHANGELOG.TXT
+++ b/CHANGELOG.TXT
@@ -42,6 +42,7 @@
 	
 	Fixes:
 	------
+	MR-872: Crash in External Tools when arguments aren't quoted
 	MR-854: crashes when right clicking on connection tab
 	MR-852: Option "Allow only a single instance of the application" non-functional
 	MR-836: Trying to delete a folder of connections only deletes 2 connections at a time
diff --git a/mRemoteV1/Tools/ArgumentParser.cs b/mRemoteV1/Tools/ArgumentParser.cs
index d79e5be4..d0dff544 100644
--- a/mRemoteV1/Tools/ArgumentParser.cs
+++ b/mRemoteV1/Tools/ArgumentParser.cs
@@ -124,11 +124,7 @@ namespace mRemoteNG.Tools
 
                 if (haveReplacement)
                 {
-                    char trailing = '\0';
-                    if (tokenEnd + 2 <= input.Length)
-                        trailing = input.Substring(tokenEnd + 1, 1).ToCharArray()[0];
-                    else
-                        trailing = string.Empty.ToCharArray()[0];
+                    var trailing = tokenEnd + 2 <= input.Length ? input.Substring(tokenEnd + 1, 1).ToCharArray()[0] : '\0';
 
                     if (escape == EscapeType.All)
                     {