User with full control on a Sp19 site gets access denied

Question

A user with full access control on a SharePoint 2019 site is getting access denied. If the user is trying to create a new item or edit an existing one, he will b redirected to the access denied page. any idea about this bug?

Answer 1

Hello @Anonymous ,

Please perform troubleshooting:

1.Sign in site as an admin and check this user permissions in site-level

2.Sign in the list page as an admin and check this user permissions in list-level

Thanks,
Echo Du

=====================
Updated Answer ====================

Hi @Anonymous ,

Make the following troubleshooting

1. Add this site to "Trusted sites"

• Open IE browser >> Internet options
• On the "Internet Options" windows >> Security >> Trusted sites >> Sites
• On the "Trusted sites" panel, add the site URL and uncheck the "Require server verification Mode" checkbox

• Click Close, and then click "Custom Level".
• On the "Security Settings - Trusted Sites Zone" panel, scroll to the vety bottom and select "Automatic logon with current user name and password" option
• Click Ok and Apply.

2. Disable LoopBackCheck with PowerShell

New-ItemProperty HKLM:\System\CurrentControlSet\Control\Lsa -Name “DisableLoopbackCheck” -value “1” -PropertyType dword  

3. Delete this user permission and re-grant user “Full Control” permission

Thanks,
Echo Du

========================

If an Answer is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.