Access Denied error in SharePoint

Issue: User getting "access denied" error even with sufficient group permission.

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Resolution:
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Remove & re add the user to group by powershell.

stsadm -o adduser -url "<<Site URL>>" -userlogin "<<Domain\account>>" -group "<<SP Group>>"

Set-SPUser -Identity '<<Domain\account>>' -Web <<Site URL>> group "<<SP Group>>"

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