Default Landing Tab Not Working in Salesforce App: How to Set the Default Tab in Classic and Lightning Experience

In order for this to function, when a User logs in they are taken to the default landing tab specified by the administrator, the tab must be set to "Default On."
 

In Salesforce Classic

1. Click on Setup.

2. In the Quick Find search box, enter Apps and click it.

3. Locate the app and click Edit.

4. Select an object as the default landing tab on the drop down arrow.

5. Assign it to Profiles.

6. Click Save.

In Lightning, administrators also need to place the custom tab at the top of the list in the app. Review Make Custom Object the default tab in Lightning​.

In Lightning Experience

1. Click the gear icon then click Setup.

2. In the Quick Find search box, enter App Manager and click it.

3. Locate the app and click the drop-down arrow on the right.

4. Click Edit.

5. Click Navigation Items.

6. Under the Selected Items section, select the custom tab and move it up to the top of the list by clicking the Move Up arrow.

7. Click Save.

Note: Administrators cannot make a tab the default for a console navigation app. This article does not work with Field Service.