sorry, that link doesn't seem to work. I don't know if the Moderators would be kind enough to fix it. For now I paste below my earlier rersponse (I also agree about keeping the door and drawer open between washes to dry it out and prevent mould growth)
"the main cause is sludge, which moulders and festers and feeds bacteria and mould.
Be aware that bleach may kill the smelly bacteria for one day, it will not remove the soapy sludge they breed on.
Accumulation of soap powder and conditioner sludge inside the tub: This is caused by one or both of adding too much (twice what it says on the box will not get clothes twice as clean) or doing lots of cold or cool washes. To wash away the soapy sludge, do a HOT wash with whatever old cotton towels you can find but NO POWDER. If it foams up, you will know it is dissolving the old soap sludge. You can add washing soda if you want, this helps dissolve soap sludge.
Soapy sludge behind the powder drawer and in the filling pipe that runs down from it. Take the drawer out to clean. Black mildew is common here. Again it is caused by soapy sludge. You can kill the black mould using a kitchen cleaner with bleach, then remove the residue by scrubbing with a nylon washing-up brush and rinsing with hot water. If you can do a Hot Fill (many machines are cold fill only) it will help.
The Soapy Sludge problem can be reduced by using tablets or liquids.
Less often, there is a greasy sludge caused by clothes and towels that have skin cream, bath oil, baby lotion etc on them. I suppose it might also happen if you work in a chip shop or lard factory and wash your overalls. A hot wash with washing soda and Ariel Liquid will clean it off.
Hot water will wash away sludge, cold water won't.
The other cause of smelly washers is dirty water from the sink flowing down the drain hose, carrying fish heads, tea leaves, sour milk etc. This happens when the washer drain hose is attached to the sink waste (it will not happen if it goes into a stand pipe). To prevent this, look at the waste hose and make sure it is looped up so the the loop goes right up to the underside of the draining board. The loop MUST go higher than the water level in the sink when it is full."