“The selected cells are read-only” error on Custom Field when trying to insert in Datasheet mode

At times , when we try to edit a list in datasheet view it gives the below error.

List Datasheet View Is Read-Only When Content Approval Is On in a Sharepoint List

How to turn off Content Approval

1. Browse to the list for which Content Approval is to be turned off.

2. Click Settings next to the Actions menu. 

3. On the dropdown menu for Settings, click List Settings.

4. In List Settings page, under General Settings, click the Version Settings.

5. On the Version Settings page, set the Require content approval for submitted items option to No and click the "OK" button.

Now you should be able to edit the list and do bulk copy-paste.

Once the editing is completed, please make sure that Content Approval Is Turned ON (as before).