I was suffering from 'smelly washing machine'. The kitchen stank of cooked greens each time I walked by the machine!! Web research tells me that it is because we are all now washing at 30 or 40 degrees. I used the product on a 90 degree service wash (no items in the machine). It helped but I actually had to use the product three times (every other day) to cure the smell as my situation was particularly bad. I shared the product with my daughter who also had the same problem and hers is ok now too. I have now reverted to washing all my 'whites' on 60 degrees and hope that the 'smelly' problem does not return. I hope this review has helped you.