Right-click on the toolbar-> customization opens a custom dialog box. The second tab of this dialog box "command (&C)" allows you to add and remove commands and buttons for the menu bar and individual toolbars, or to reset to the default.
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Additions and deletions already have commands and buttons:
Simply select the toolbar or menu bar that you want to change on the left Drop-down list and the normal list, and then select or clear the check box on the right button or command.
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To add an existing Select all feature button:
Right-click on the toolbar, select Custom, and on the left side of the Open dialog box, on the command bar (&B): Select Main Menu bar in the Drop-down list, click Edit in the lower left list, and right-click the &l command on the right, and select Copy to (&C) in the pop-up menu ... ", select the target toolbar in the pop-up dialog box.
If you don't like it now it appears as text by default, and you can open an Edit dialog box by double-clicking it in the Customize dialog box. You can select the display name, icon, and shortcut key for the New button in this dialog box, and specify how it will be displayed.
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Add Self button: here to add a button to open "calculator" for example.
Click the + button in the lower-right corner of the commands (&c) tab of the Customize dialog box, select the added Target toolbar location on the left side of the Add dialog box that appears, select New button on the right, and click OK to close the Add dialog box.
Now find the newly added button on the right side of the Customize dialog box, adjust its position with a button with up and down arrows, and then double-click or right-click the New button, select Edit (&e) from the pop-up menu, and open the Modify Command Entry dialog box.
Now add the command to execute after you click the New button. Enter C:windowssystem32calc.exe in the Hyperlink text box or click the Select (&s) |v button-Open file (&o) to locate the calculator, and close the dialog box when finished.
Now you can see the button on the toolbar and click it to run Calculator.