diff --git a/install.uefi b/install.uefi
index 42bca0a..b3c0b69 100644
--- a/install.uefi
+++ b/install.uefi
@@ -159,9 +159,15 @@ if [[ "${UNKNOWN_PARTITIONS}" > "0" ]]; then
   fi
 fi
 
-mkfs.vfat -n EFI -F 32 /dev/vda1
-mkfs.ext4 -L usr /dev/vda2
-mkfs.ext4 -L root /dev/vda4
+# Großbuchstaben in UUIDs zu kleinbuchstaben umwandeln
+UUID_ESP="${UUID_ESP@L}"
+UUID_ROOT="${UUID_ROOT@L}"
+UUID_USR="${UUID_USR@L}"
+UUID_USRHASH="${UUID_USRHASH@L}"
+
+mkfs.vfat -n EFI -F 32 "/dev/disk/by-partuuid/${UUID_ESP}"
+mkfs.ext4 -L usr "/dev/disk/by-partuuid/${UUID_USR}"
+mkfs.ext4 -L root "/dev/disk/by-partuuid/${UUID_ROOT}"
 
 mount /dev/disk/by-label/root /mnt
 mkdir -p /mnt/{boot,usr}