diff --git a/01-install-base-files b/01-install-base-files
index c513f3b..0eb2f32 100755
--- a/01-install-base-files
+++ b/01-install-base-files
@@ -5,13 +5,13 @@ umask 022
 # Create /opt directories.
 mkdir -p -m 755 {/opt,/opt/{bin,include,info,lib64,man,man/man{0..8},sbin,share}}
 
-# Install the LetsEncrypt CA bundles, to stop wget moaning.
+# Install the CA bundles, to stop wget moaning.
 cp -R ca-certificates /usr/local/share
 update-ca-certificates
 
 # Install memtest86 into /boot.
 # Only install if /boot exists, so we are container compatible.
-[ -e /boot ] && cp memtest86+ /boot
+[[ -e /boot ]] && [[ ! -e /boot/efi ]] && cp memtest86+ /boot
 
 # Install root's new crontab.
 cat root.crontab >/var/spool/cron/crontabs/root