Quick Actions or the plus Icon on Email Integration Side Panel Does Not Show

Verification to ensure the desired results from the publisher action for Gmail Integration or Outlook Integration side panel 

Step 1: Make sure that the publisher actions are enabled for Chatter. Refer to Enable Actions in the Chatter Publisher. 

If you haven’t created a global 'Create a Record' actions for the kinds of records you want available to your Users, you have to do so now.

Step 2: 
 

1. Verify that you’ve set up Create a Record global action for each publisher action you want to be available in your Users’ side panel publisher menus. For more, please review Create Quick Actions for the Salesforce Side Panel Publisher.
2. Add the publisher actions to the appropriate publisher layout.
3. For Group, Contact Manager, or Professional Editions, you add publisher actions to your Users’ side panel publisher menus with the global publisher layout editor. For more, please review Create Global Publisher Layouts. If you’re already using the global publisher layout for other Salesforce features, you notice that any publisher actions you add for the side panel are displayed for all features. The side panel publisher, however, displays only actions with the action type Create a Record.
4. For Enterprise, Performance, Unlimited, or Developer Editions, you add publisher actions to your Users’ side panel publisher menus with the side panel publisher layout editor. You can also create multiple side panel publisher layouts to give different users access to different side panel publisher menus. 

Step 3:
 

1. From the Salesforce application, go to

2. Click Edit in front of the Action. For example, New Case.
3. If the Case object has record types, a Record Type field shows up. Select a record type other than Master.
4. Click Save.
5. In the layout editor, drag fields that you want to show or hide on the action
6. Save the layout.

Step 4: If you’re still not able to see the publisher action in Gmail Integration or Outlook Integration side panel, create a new action and include the same in the global publisher layout or side panel publisher layout.
 

1. Go to

2. Click New Action.
3. Select Action Type: Create a Record.
4. Only Create Record actions appear in the side panel publisher menu.
5. Select a Target Object for the type of record you want available to Users with this action. If the Target Object has more than one record type, make sure that the Users you assign to this action also have access to that record type. Then, select a record type other than Master.
6. Enter a Label for the new action that tells your Users what it does.
7. Click Save.
8. From the Action Layout Editor, drag the fields you want to appear on the side panel publisher record detail page. Note: If any of these fields are marked as required for this type of record elsewhere in your organization, make sure to include the fields in this action, too. This is because Salesforce prevents your Users to save records from the side panel publisher if the required fields aren’t included in the record detail. The action layout editor displays red asterisks next to required fields.

                       
For more, please review Create Quick Actions for the Salesforce Side Panel Publisher.

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All of the above-provided troubleshooting steps can assist in various scenarios that involve the publisher action in the side panel.