You may have picked up the wrong detergent for your high-efficiency (he) washer - that's an easy thing to do; I've done it more than once. The he symbol is not as easy to notice and when you grab a few bottles off the shelf, it can happen that there's a stray in the mix. You may be tempted to use it rather than return it. After all, what difference can it make to use a non-he detergent in an he washer? Lots! There are good reasons to use only he detergents; find out in he Detergents vs Regular Detergents.
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