Require Users to Assign an ID When Creating New Customer Records
When users do not want to use Auto-Generated Numbers and instead want to manually enter a value for Customer ID field when creating new customers, the following steps must be done:
1. Navigate to Setup > Company > General Preferences. 2. Locate the Auto Name Customers checkbox and uncheck it. 3. Click Save. 4. Navigate to Setup > Company > Auto-Generated Numbers. 5. Under Entities tab, uncheck the Enable checkbox for Customer. 6. Click Save.