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Step 1. Choose the field type

Data Type: Formula

Next

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Step 2. Choose output type

Field Label: AP Last updated

Field Name: SUBS_APLastUpdated

Formula Return Type: Date/Time

Next

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Step 3. Enter formula

Select the Simple Formula tab

Select Field Type: Opportunity

Insert Field: -- Insert Merge Field --

AP Last Updated (Date Time)= : TSPC__CPAccountPlan__r.LastModifiedDate

Click the 'Check Syntax' button to ensure there are no errors

Description: Fill in as needed

Help Text: Fill in as needed

Next

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Step 4. Establish field-level securityLeave as is or modify as needed

Select the needed Field Level Security for Profile (To select All, click the 'Visible' box on the column header until all boxes are checked)

Set all selected to 'Read Only' or as desired.

Next

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Step 5. Add to page layouts

Leave as is or modify as needed

Save

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Add AP Last Updated to the Account Header

Go to the Gear Icon > Setup > Object Manager > Account > Compact Layout

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If the only Compact Layout is ‘System Default’

Clone the Layout and assign a new name. e.g. New Header

Or, add the new Field to an existing Compact Layout

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Add the new Field to the Compact Layout

Open the new Compact Layout and click Edit.

Move the Field from Available Fields to Selected Fields.

Save

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Note: The Compact Layout selected as Primary is the layout that will be displayed on the Account Page.

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