diff --git a/app/helpers/dmsf_upload_helper.rb b/app/helpers/dmsf_upload_helper.rb
index aacc8f98..f11e9477 100644
--- a/app/helpers/dmsf_upload_helper.rb
+++ b/app/helpers/dmsf_upload_helper.rb
@@ -207,6 +207,7 @@ module DmsfUploadHelper
 
   # 1 -> 1, -65 -> A
   def self.gui_version(version)
+    version = version.to_i # catch the case where version is a BigDecimal
     return version if version >= 0
     (-version).chr
   end