Usually, the E25 fault code appears when the impeller is jammed with a foreign object or piece of debris (shard of glass, chipped china, etc.)
Remove the filter above the pump and open the pump cover. The cover can be held by screws or clips. Check the impeller and use pliers or tweezers if necessary. When the foreign object, if any, is removed, check the impeller by rotating it with your hand. When placing the filter and pump cover back, make sure the blue arrows are aligned properly. This should prevent debris and foreign objects from blocking the impeller.
Many people integrate their dishwashers with sink units. Not infrequently, drain pipes get clogged, twisted, trapped, etc. Clogs form when pieces of food get into the waste pipe. Fat may build up in it and impede the draining process. All this may cause your dishwasher to fail to empty. Check all pipes on a regular basis and clean them regularly using appropriate tools and detergents.
Also, E25 occurs when there is a problem with the pump. Modern pumps have armature inside the housing. Sometimes, seals deteriorate and let water through. This can cause the pump to work intermittently of fail completely.