...
- Click Settings from SF (the Gear icon in the upper right-hand part of the screen) -> click Setup
- Setup Home screen opens. From the left panel, under ADMINISTRATION, Users -> click Users
- Find the System Administrator profile and click to open it
- Click Clone. Clone Profile screen opens
- Add the following Profile Name: SystemAdminWithCreatedBy and click Save
- The newly created Profile SystemAdinWithCreatedBy opens. Scroll down to System and click on System Permissions
- Click Edit
- Scroll down to Set Audit Fields upon Record Creation (Set audit fields, such as Created By and Last Modified By, when you create a record (API only).) and put the tick
- Scroll up and click Save. Permission Changes Configuration window opens. Click Save again
- On the left panel, under ADMINISTRATION click Users. Find your System Administrator and click Edit next to the entry
- Setup Users screen opens. Change the Profile from System Administrator to the newly created Profile SystemAdminwithCreatedBy and click Save
...