Rule type: Replace Header

Header Field: User-Agent

Match String: /^.*$/

Replace with: Mozilla/5.0 (Windows; U; MSIE 9.0; WIndows NT 9.0; en-US)

You can view examples of User-Agent strings at the following link: http://www.useragentstring.com/pages/useragentstring.php

Start Regex: /

Start Match: ^

Wildcard: .*

End Match: $

End Regex: /