Sometimes mice can be very delicate when taking the bait on traps... so delicate they don't trigger them. You need to set the traps as hair trigger as possible to increase the odds of catching the mouse. What can help is to put the trap inside a narrow box on its side, forcing the mouse to walk over the mechanism to reach a tasty morsel of cheese or peanut butter on the trap. It can also help if you fix the bait to the trap with a little tape so it is more difficult for the mouse to just lick or nibble the bait. The more effort the mouse has to make to get to and remove the bait the better. Having said that the bait still needs to be visible and smell attractive to the mouse, so don't cover it up too much.
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I've left WP indefinitely.