diff --git a/compat/mingw.c b/compat/mingw.c
index 4201db9660..02b1c54569 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3121,9 +3121,7 @@ int is_path_owned_by_current_sid(const char *path, struct strbuf *report)
 				    DACL_SECURITY_INFORMATION,
 				    &sid, NULL, NULL, NULL, &descriptor);
 
-	if (err != ERROR_SUCCESS)
-		error(_("failed to get owner for '%s' (%ld)"), path, err);
-	else if (sid && IsValidSid(sid)) {
+	if (err == ERROR_SUCCESS && sid && IsValidSid(sid)) {
 		/* Now, verify that the SID matches the current user's */
 		static PSID current_user_sid;
 		BOOL is_member;
diff --git a/setup.c b/setup.c
index 1159873da9..d96de2a34e 100644
--- a/setup.c
+++ b/setup.c
@@ -1781,10 +1781,19 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		break;
 	case GIT_DIR_INVALID_OWNERSHIP:
 		if (!nongit_ok) {
+			struct strbuf prequoted = STRBUF_INIT;
 			struct strbuf quoted = STRBUF_INIT;
 
 			strbuf_complete(&report, '\n');
-			sq_quote_buf_pretty(&quoted, dir.buf);
+
+#ifdef __MINGW32__
+			if (dir.buf[0] == '/')
+				strbuf_addstr(&prequoted, "%(prefix)/");
+#endif
+
+			strbuf_add(&prequoted, dir.buf, dir.len);
+			sq_quote_buf_pretty(&quoted, prequoted.buf);
+
 			die(_("detected dubious ownership in repository at '%s'\n"
 			      "%s"
 			      "To add an exception for this directory, call:\n"