diff --git a/src/install/default.txt b/src/install/default.txt
index eb01df05..d90b3188 100644
--- a/src/install/default.txt
+++ b/src/install/default.txt
@@ -533,7 +533,9 @@ main() {
   case "${croc_os}" in
      "Darwin" ) croc_os="macOS";;
     "CYGWIN"* ) croc_os="Windows";
-                croc_dl_ext="zip";;
+                croc_dl_ext="zip";
+                print_message "== Cygwin is currently unsupported." "error";
+                exit 1;;
   esac
 
   case "${croc_arch}" in