Answer: You can add a commercial compost starter, like Gardener's Supply's "Super Hot Compost Starter" (their ph# is 1-800-863-1700). Or you can simply add some garden soil and/or aged manure. I'm not sure why you need to do this--or how yourcompost became sterile--so it's hard to answer your 2nd question. Beneficial microorganisms are present in soil; in compost their numbers are increased since there is a ready source of food for them. If you spread your sterile compost in your garden, microorganisms will naturally be drawn there and multiply.
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