Create an AutoExec macro that runs when the DB is opened

From:

https://support.office.com/en-us/article/Create-a-macro-that-runs-when-you-open-a-database-98ba1508-dcc6-4e0f-9698-a4755e548124

Create an AutoExec macro:

If you have already created a macro that contains the actions that you want to occur when the database starts, just rename the macro AutoExec, and it will run the next time that you open the database. Otherwise, follow these steps to create a macro:

1. On the Create tab, in the Other group, click Macro. If this command is unavailable, click the arrow beneath either the Module or the Class Module button, and then click Macro.
2. In the Macro Builder, in the first empty Action cell, select the action that you want to perform. If applicable, under Action Arguments, type the appropriate values in the argument boxes.
   If you cannot find the action you want, on the Design tab, in the Show/Hide group, make sure Show All Actions is selected. This expands the list of actions that you can use, but the list will include some actions that will only run if the database is granted trusted status. For more information, see the articles Decide whether to trust a database or How database objects behave when trusted and untrusted.
3. Repeat step 2 for each additional action you want to occur.
4. Click Save, and in the Save As dialog box, type AutoExec.
5. Click OK and then close the Macro Builder. The new macro will run the next time that you open the database.

For more information about how to create macros, see the article Create a macro.

NOTE: 

• To bypass the AutoExec macro and other startup options, hold down the SHIFT key while you start the database. For more information, see the article Bypass startup options when you open a database.
• Another way to perform actions when a database starts is to specify a startup form, and then attach macros or VBA code to the OnOpen or OnLoad events of the form. For more information, see the article Set the default form that appears when you open a database.