diff --git a/repertory.iss.in b/repertory.iss.in
index 9ffd4606..1f425ed4 100644
--- a/repertory.iss.in
+++ b/repertory.iss.in
@@ -68,4 +68,4 @@ Filename: "msiexec.exe"; WorkingDir: "{app}"; Parameters: "/a winfsp-@WINFSP_VER
 [Registry]
 Root: HKLM; Subkey: "SYSTEM\CurrentControlSet\Control\Session Manager\Environment"; \
     ValueType: expandsz; ValueName: "Path"; ValueData: "{olddata};{app};"; \
-    Check: CheckAddPath("{app}")
+    Check: CheckAddPath(ExpandConstant('{app}'))