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In the Entity field, select an entity of your company which is responsible for the document. The Entity field is available if the Multi-Company Accounting option is selected on: Administration > Settings > General Settings. You can select your personal default entity to appear in documents; for this, refer to Personal Settings. If you have not selected your default entity, the entity defined first will be used as the system default value.
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After filling out the tab, click the Save button to save your work. After filling out all the tabs, click Post to post the document without closing it or Post and close to post and close the document.
or descriptions of other buttons, see Document Toolbar.