Hi I've had this trouble with my dishwasher. Mine's just over a year old, so out of warranty. We blew through the pipes. they weren't blocked, then we checked the pump, and that seemed ok. I opened the salt container at the bottom, and it was full up with water, and it really smelt bad.
We tried to clear out as much as we could and left it all overnight to dry. I've put some salt in it this morning and run a prewash cycle(the shortest) and it finished it. I've now just run a fast & dry cycle and it has now finished that as well.
This seems to have fixed it, I've now run several cycles since and it's working perfectly now. I read on another site somewhere about dishwashers still needing salt even though these tabs all say that they have enough salt in them.
Not sure if I'm allowed to post the link but I'll try http://www.dishwasher-care.org.uk/best.html.
Fingers crossed it works for you as well! By the way, it took nearly a kg bag of dishwasher salt and mine is a slimline one.
Bev Young, June 2007