I want to set the opening balances for customers and suppliers without affecting the income statement

can’t find starting date in setting (desktop)

There is no [starting date] in [setting].

You can find [Starting Balances] in [Settings].

Or may be you mean to set the period for the summary:

I want to set the opening balances for customers and suppliers without affecting the income statement.

Just add the unpaid Sales and Purchase invoices - the invoice date should be earlier than the start date of the Period in your Summary Screen

That way the sales and purchase amounts do not affect your income and expenditure accounts but only the balances on the Customer and Supplier accounts

I would have directed you to the guides, but unfortunately they return a 404 error, Page Not Found.

Guides will give you a 404.

Create a new sales invoice for each customer. Make sure you select the customer in the customer field. The Date of the invoice should be your starting date, and the description can be Opening balances as at … .Leave the item column empty and select the retained earnings in the accounts column. Type the total amount in the Unit price column and create. This will report the amounts in the customer records and the corresponding entries will be in your retained earnings account. Enter supplier balances in the same way using purchase invoices

The better way is to enter the actual unpaid invoices with their real date - this will be earlier than your start date obviously

That way as they are paid you can keep track of which invoices are still outstanding

Also your customer and supplier statements will properly reflect the transactions