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Since your last boot scan found nothing ......
No, it is safe to leave them in the chest for as long as you want. Infected files in the chest can do no harm. Normally, we suggest leaving them in the chest for 2 weeks. After 2 weeks and your computer is running fine, re-scan them while in the chest ... right click each file and choose Scan. If these files are still showing infected, then delete them from the chest if you want and this will permanently delete them from your computer.
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