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With UMS version 6.05.100, the evaluation of UMS permissions has changed: If you set Deny on a node, you cannot set Allow permission on a subnode. The Allow checkbox is not editable.
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Solution
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Check → Check the permissions in the Access Control dialog. If the Allow permissions should be given for a subnode, do not set any permissions for the node.
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Open the Access Control dialog for a node, Profiles in this case.
Disable checkboxes Allow and Deny.
The Effective Rights read now "not set".
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Open the Access Control dialog for a subnode, for which premissions should be granted. In our case, it is the folder "Languages".
Set the required permissions and save the settings.
The user can only browse up to the subnode "Languages", for which the access rights have been given.