Its a stupid maya bug. You need to delete the cache through the solver menu, then disable the cache...which, byt the way, does not fully disable it, hence you are getting the cache recreating itself. So next you have to open up the solver disk cache properties from the menu (think its the bottom option) then switch off the check box so all the cache properties are ghosted. Should work now. Failing that, do all that again and then save the scene as a new name. Its really thick I know, Alias have never fixed this. It may be worth while for the future, for you to just write some mel and design your own particle caching system. I know several people who have gone to this extent in the past cos they were so fed up with Maya's acrappy cache system.