diff --git a/ubuntu/1-pre-install.sh b/ubuntu/1-pre-install.sh
index 169d3dc..416fc82 100644
--- a/ubuntu/1-pre-install.sh
+++ b/ubuntu/1-pre-install.sh
@@ -91,7 +91,7 @@ fi	# if erase all
 
 # ----- Open the LUKS partition -----
 # Open the crypt partition. 
-printf %s "${PASSPHRASE}" | cryptsetup open -e - "${DEV}${CRYPTPARTITION}" ${CRYPTPARTNAME}
+printf %s "${PASSPHRASE}" | cryptsetup open -d - "${DEV}${CRYPTPARTITION}" ${CRYPTPARTNAME}
 
 # Check whether successful open. If mapped, it is successful. 
 if [ ! -e /dev/mapper/${CRYPTPARTNAME} ] ; then 
diff --git a/ubuntu/3-post-install.sh b/ubuntu/3-post-install.sh
index c417ead..89b12e1 100644
--- a/ubuntu/3-post-install.sh
+++ b/ubuntu/3-post-install.sh
@@ -37,7 +37,7 @@ chmod u=rx,go-rwx /etc/luks
 chmod u=r,go-rwx /etc/luks/boot_os.keyfile
 
 # Add a key to the key file. Use the passphrase in the environment variable. 
-printf %s "${PASSPHRASE}" | cryptsetup luksAddKey -e - "${DEV}${CRYPTPARTITION}" /etc/luks/boot_os.keyfile
+printf %s "${PASSPHRASE}" | cryptsetup luksAddKey -d - "${DEV}${CRYPTPARTITION}" /etc/luks/boot_os.keyfile
 
 # Add the LUKS volume information to /etc/crypttab to decrypt by kernel.  
 echo "${CRYPTPARTNAME} UUID=$(blkid -s UUID -o value ${DEV}${CRYPTPARTITION}) /etc/luks/boot_os.keyfile luks,discard" >> /etc/crypttab