diff --git a/PROMS/ReferencedObjects/Exe/RefObj/ROEditor/RO_FST.cs b/PROMS/ReferencedObjects/Exe/RefObj/ROEditor/RO_FST.cs
index 93c93986..b652b0f6 100644
--- a/PROMS/ReferencedObjects/Exe/RefObj/ROEditor/RO_FST.cs
+++ b/PROMS/ReferencedObjects/Exe/RefObj/ROEditor/RO_FST.cs
@@ -786,7 +786,7 @@ namespace ROEditor
 
 			//Write the RO's record ID
 			string RecIdStr = elem.GetAttribute("RecID");
-			RORecID = System.Convert.ToUInt16(RecIdStr,16);
+			RORecID = System.Convert.ToUInt32(RecIdStr,16);// B2019-105 Corrected conversion to 32 bit
 
 			fhFST.Write(RORecID);
 
@@ -805,7 +805,7 @@ namespace ROEditor
 
 			//Write the parent ID
 			string ParIDstr = elem.GetAttribute("ParentID");
-			ParID = System.Convert.ToUInt16(ParIDstr,16);
+			ParID = System.Convert.ToUInt32(ParIDstr,16);// B2019-104 Corrected to 32 Bit
 			fhFST.Write(ParID);
 
 			// not sure why, was in old FST code but no comment!