Since SAP S/4 no longer supports sales activities, a new object – E4C Activity has been created, with proper transactions to manage it. It's recommended to all FSM Cloud Connector users to use solely this new object. Already existing sales activities can be easily transformed into E4C activities with the migration program.
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Enable the 'E4C Activity' flag before running the migration program. The activity type cannot be determined unless the E4C Activity flag is switched on in transaction /PACG/ECM_CPROP - General Properties of E4C.
Migration Program Details
The migration program can be found in /PACG/ECE package (program /PACG/ECE_ACTIVITY_TRANSFER). 
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Activities to migrate are defined using Sales Organization number, Distribution Channel number, Division number, Sales activity number or creation date. 
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Inb. Data Create.Class - Change 'Incoming Message Attributes' for the message type /PACG/ECM_ACTIVITYIN (New Inb. Data Creation class: /PACG/ECM_CL_S_IDOC_I_ACTIVI_E)
IDOC Creation Class - Change the 'Outgoing Class Assignment' for message type /PACG/ECM_ACTIVITYOUT (New Idoc Class: /PACG/ECM_CL_S_IDOC_O_ACTI_E)
Change IDOC processing class – after successful migration the checkbox should be checked to automatically update the classes for the configuration (the classes should be entered in the 'configuration update' section). With this setting new activities won't be transferred/created. If no data is entered, the program will migrate all the sales activities found. The number of activities to transform is displayed in a warning window.
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Displayed logs confirm successful transformation for a given activity. All the logs can be found in /pacg/ece_acttr table (E4C: Log table with migrated sales activities).
Sales activities are stored in VBKA table. If the migration process succeeded, these activities can now be found in /PACG/ECM_ACTI table. If no fitting activity is found, an error log is displayed.
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If the 'Test run' checkbox is checked, the program will display logs showing which activities can be transformed, have already been processed or can't be mapped, but no changes will be made in the database. 
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Post Migration
Set up the configuration for the E4C activity for your business process if its not set up already.
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After the transformation process, regardless of its success, subroutine manage_number_ranges is carried out, assuring the activity number range status is equal to the highest sales activity number range status. Number range objects are maintained in transaction SNRO.
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Let's access sales activity 100001720 via transaction VC03.
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This activity can't be found in /PACG/ECM_ACTI_VC03 - Display E4C Activity transaction.
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Once the migration process has been launched for this activity, a confirmation log can be seen. 
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The activity can now be seen as an E4C Activity in transaction /PACG/ECM_ACTI_VC03. 
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