No they should not both be running in the background. Disable the background scanning in Windows Defender.
But there's nothing to prevent you using Windows Defender as a manual scanner, once a week or so.
Mark
I have an hp laptop, windows 7 ......
should I run both windows defender and norton internet security? Would running both slow my computer? If I should only run one program, which is the best?
Thanks
fishintopsail
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