The Generate Rows screen is used to easily add rows per account and automatically configure its account filter. Also, each row generated will have Calculation row type. If in any instance you will want to change this to either Hidden or Cash Flow Activity row type, you can do so without worrying of losing the Account Filter because it will be preserved.
It is only when changing this row to other row types other than Hidden and Cash Flow Activity, i21 will show this message. And be warned, once Yes is clicked here, it will delete the Account Filter on the selected row and you will not be able to restore it. 
The following steps will guide you on how to generate rows.
- Add a new row designer record.
- Click Generate Row toolbar button and Generate Rows screen will open.
- Click New toolbar button.
- In the Account Filter field, select:
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