diff --git a/all.sas b/all.sas
index 4568684..aff99c2 100644
--- a/all.sas
+++ b/all.sas
@@ -2226,7 +2226,7 @@ Usage:
 %let infound=0;
 %let outfound=0;
 data _null_;
-  set sashelp.vextfl(where=(upcase(fileref)="&inref" or fileref="&outref"));
+  set sashelp.vextfl(where=(fileref="&inref" or fileref="&outref"));
   if fileref="&inref" then call symputx('infound',1,'l');
   if fileref="&outref" then call symputx('outfound',1,'l');
 run;
diff --git a/base/mp_base64copy.sas b/base/mp_base64copy.sas
index 2cb7c0c..ec81f58 100644
--- a/base/mp_base64copy.sas
+++ b/base/mp_base64copy.sas
@@ -53,7 +53,7 @@
 %let infound=0;
 %let outfound=0;
 data _null_;
-  set sashelp.vextfl(where=(upcase(fileref)="&inref" or fileref="&outref"));
+  set sashelp.vextfl(where=(fileref="&inref" or fileref="&outref"));
   if fileref="&inref" then call symputx('infound',1,'l');
   if fileref="&outref" then call symputx('outfound',1,'l');
 run;