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For example, you can limit submission access to users who are logged in, to collect data without asking for it within the form.
Configuring Submission Access
From the administration bar, select Workbench, and then select My Dashboard.
Navigate to the Forms list.
Locate the form you want to configure and select Settings from the drop-down menu under the Operations column.
Under the Settings tab, select the Access sub-tab.
Under Create Submissions, select the types of users who can view and submit the form. Note: Webform submission access defaults to Everyone.
Optionally, specify which authenticated users you would like to view, delete, and/or purge submissions and test the web form.
Select Save.
Available groups
Everyone: Anyone can view and submit this webform.
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