Hello David Lindsey,
Thank you for posting in Q&A forum.
1.Please check if you have change permissions on this folder you mentioned.
Right click this folder\Advanced button\Effective Access\select a user (type your account) \ click "View effective access" button.
And check if you have "Change permissions" on this folder (X means there is no permission).
2.If there is no change permission for your account on this folder.
You can add "Change permissions" for your account on this folder.
Click Security tab\Advanced button\Add button
Principle: your account
Type: Allow
Applies to: This folder, subfolders and files
Clear all permissions and check "Change permissions".
3.Check if you can change permissions on this folder.
Hope the information above is helpful.
If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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