How to convert *.txt file into Unicode

I have a requirement where a client will supply a file in encoding ANSI, but my system can only successfully read a file in UNICODE. So how do I tackle this issue? I know when I "save as" the file into as UNICODE encoded the file gets picked up. It's difficult to make the client comply with our request. So can I have any batch program for this folder to convert this file into UNICODE and then pick up?

From stackoverflow

• recode could do the job.

• iconv can do that:

  Usage: iconv [OPTION...] [FILE...]
  Convert encoding of given files from one encoding to another.
  
   Input/Output format specification:
    -f, --from-code=NAME       encoding of original text
    -t, --to-code=NAME         encoding for output
  
   Information:
    -l, --list                 list all known coded character sets
  
   Output control:
    -c                         omit invalid characters from output
    -o, --output=FILE          output file
    -s, --silent               suppress warnings
        --verbose              print progress information
  
    -?, --help                 Give this help list
        --usage                Give a short usage message
    -V, --version              Print program version
  
  Mandatory or optional arguments to long options are also mandatory or optional
  for any corresponding short options.
  
  For bug reporting instructions, please see:
  <http://www.gnu.org/software/libc/bugs.html>.
  

• You can also easily convert encodings in python:

  inf = open("infile.txt")
  data = inf.read().decode("latin1")
  inf.close()
  
  outf = open("outfile.txt", "w")
  outf.write(data.encode("utf-8"))
  outf.close()
  

• Here's a Powershell solution

  $lines = gc "pathToFile"
  $lines | out-file -enconding Unicode
  

• Neither ANSI nor Unicode are encodings.You'll have to know the ANSI codepage of the input file and the Unicode encoding (UTF8 or UTF16 - LE or BE) before you can use one of the suggested tools (such as iconv)

  Joe Pineda : Wish I could upvote this more. For most Windows users, "Unicode" means UTF32. Most western European languages use Latin1 codepage, so most people assume that's "ANSI" encoding (again, I blame MS for their word usage in their "Save As" options).

  Joe Pineda : We could add that looking into Control Panel->Regional Settings->Advanced Options will show which ANSI code-pages are installed and used.

  Alan Moore : On Windows systems, "Unicode" usually means UTF-16.