diff --git a/lisp/server.el b/lisp/server.el
index 20fa27c20bf..35243aeb90e 100644
--- a/lisp/server.el
+++ b/lisp/server.el
@@ -1172,8 +1172,7 @@ The following commands are accepted by the client:
                    ;; Allow Cygwin's emacsclient to be used as a file
                    ;; handler on MS-Windows, in which case FILENAME
                    ;; might start with a drive letter.
-                   (when (and (eq system-type 'cygwin)
-                              (fboundp 'cygwin-convert-file-name-from-windows)
+                   (when (and (fboundp 'cygwin-convert-file-name-from-windows)
                               (string-match "\\`[A-Za-z]:" file))
                      (setq file (cygwin-convert-file-name-from-windows file)))
                    (setq file (expand-file-name file dir))