How to write a letter of complaint

Read these instructions about sample letters of complaint. When you feel confident about writing your own, do it and publish it in the Comments textbox here. This is the complaint you must make:

You ordered some software for you computer by Internet. When you got the CD, it didn’t work on your computer. Write a complaint email to the company from which you bought it asking for a refund or for a brand new CD. 120-180 words.

Preintermediate level.