diff --git a/SPT.ProfileConverter/Converters/ThreeEightToThreeNine.cs b/SPT.ProfileConverter/Converters/ThreeEightToThreeNine.cs
index 88c384c..5152f85 100644
--- a/SPT.ProfileConverter/Converters/ThreeEightToThreeNine.cs
+++ b/SPT.ProfileConverter/Converters/ThreeEightToThreeNine.cs
@@ -13,6 +13,11 @@ public override ConversionStatus ConvertProfile(string FullFilePath)
             reader.FloatParseHandling = FloatParseHandling.Decimal;
             var jsonObj = JObject.Load(reader);
 
+            if (jsonObj["info"]["ProfileConvertedFrom38"] != null)
+            {
+                return new ConversionStatus { Successful = false, Result = "This profile has already been converted!" };
+            }
+
             // Add profile converted marker to the info object.
             var info = jsonObj["info"];
             if (info != null)