Mass Data Maintenance workcenter is missing in the system. It is not possible to find the work center in the Access Rights of the Business Users.
The reason that the Mass Data Maintenance work center is not available is that below scoping elements are not scoped in your system.
Activity Management (Sales --> Account and Activity Management)
Opportunities (Sales --> New Business)
Service Request Management ( Service --> Customer Care)
Scope atleast one of the above scoping element and this will enable the Mass Data Maintenance work center in your system.
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