How to list all files and folders present in a hard disk using batch commands?

I am trying to print list of all the files and folders present in different partitions of hard disk using :

for %d in (a b c d e f g h i j k l m n o p q r s t u v w x y z) do (ifexist %d: (dir %d:/s >> %Systeminfo_TXT%))

but this doesn't print any output ?

Where am i going wrong !!

• Did you define the variable %Systeminfo_TXT%?

• The "ifexist" command is not valid in batch files. Instead, you can
  use the "if" command with the "exist" operator to check if a drive
  exists.

  for %%d in (a b c d e f g h i j k l m n o p q r s t u v w x y z) do (
  if exist %%d: (
  dir %%d:\ /s >> %Systeminfo_TXT%
  )
  )