diff --git a/makepanda/makepanda.py b/makepanda/makepanda.py
index 184803a879..b2db4ddc5c 100755
--- a/makepanda/makepanda.py
+++ b/makepanda/makepanda.py
@@ -4811,6 +4811,7 @@ def MakeInstallerOSX():
     print >>preflight, "bpfile = open(bash_profile, 'w')"
     print >>preflight, "bpfile.write(newbpdata)"
     print >>preflight, "bpfile.close()"
+    preflight.close()
     oscmd("chmod +x dstroot/scripts/uninstall16/preflight")
     
     oscmd("chmod -R 0775 dstroot/*")