diff --git a/tests/data/mod1a.mod b/tests/data/mod1a.mod
index 8e74f3e1ac135645b7067ab785619c2949c056b2..cf227651c72f92c2323a5f0d74299e1c532326ad 100644
--- a/tests/data/mod1a.mod
+++ b/tests/data/mod1a.mod
@@ -20,4 +20,4 @@ end;
 
 varobs dx dy;
 check;
-estimation(datafile=test,nobs=1000,mh_replic=2000,mh_jscale=1.3);
\ No newline at end of file
+estimation(datafile='test.xls',nobs=1000,mh_replic=2000,mh_jscale=1.3);
\ No newline at end of file