This script uses ForFiles to remove old files based on age. However, you must have forfiles installed. Windows 2003 and above have it by default

The Syntax is: 

FORFILES -p "Path to the folder" -s -m *.txt -d   -c "cmd /c del @path"

Example:

REM  Delete all BAK files from folder C:\backup  that are 5 days or older

FORFILES -p "C:\backup" -s -m *.bak -d -5 -c "cmd /c del @path"