diff --git a/post-install.sh b/post-install.sh
index e1aa6496..7d31f071 100644
--- a/post-install.sh
+++ b/post-install.sh
@@ -24,6 +24,20 @@ doas cryptboot umount
 # Configure custom-efibackup.sh
 doas sh -c '{
   echo "#!/bin/sh"
+  echo ""
+  echo "set -e"
+  echo "if /usr/bin/mountpoint -q /efi"
+  echo "then"
+  echo "  /usr/bin/umount -AR /efi
+  echo "fi"
+  echo "if /usr/bin/mountpoint -q /.efi.bak"
+  echo "then"
+  echo "  /usr/bin/umount -AR /.efi.bak
+  echo "fi"
+  echo "if /usr/bin/mountpoint -q /boot"
+  echo "then"
+  echo "  /usr/bin/umount -AR /boot
+  echo "fi"
   echo "/usr/bin/cryptboot mount"
   echo "/usr/bin/mount /.efi.bak"
   echo "/usr/bin/rsync -aq --delete --mkpath /.efi.bak/ /.efi.bak.old"
@@ -33,7 +47,6 @@ doas sh -c '{
   echo "  /usr/bin/rsync -aq --delete --mkpath /.boot.bak/ /.boot.bak.old"
   echo "fi"
   echo "/usr/bin/rsync -aq --delete --mkpath /boot/ /.boot.bak"
-  echo "/usr/bin/cryptboot umount"
   echo "/usr/bin/umount /.efi.bak"
 } > /etc/pacman.d/hooks/scripts/custom-efibackup.sh'
 doas chmod 744 /etc/pacman.d/hooks/scripts/*.sh