I switched from quickbooks desktop to quickbooks online, and old transactions that have already been recoiled imported into quickbooks online register. H

It's important to ensure that you transferred your data correctly by running the Profit and Loss report, @weslaughton.

Before you delete your old transactions, I'd suggest verifying your Profit and Loss and Balance Sheet reports in both products. You'll have to filter the date period to All Dates and the accounting method to Accrual. Check out this article: What to Do After Converting from QBDT for Windows to QBO.

Additionally, deleting reconciled transactions will cause beginning balance issues. You can refer to these articles for more info:

• Fix issues the first time you reconcile an account in QuickBooks Online
• Fix issues for accounts you've reconciled in the past in QuickBooks Online

I've included the instructions below on how to delete old transactions:

1. Go to the Sales or Expenses menu.
2. Find and open the transaction.
3. Review the transaction. Make sure you need to void or delete it.
4. If you want to include the void or delete date, add a note to the Memo or Message section.
5. Select More in the footer. Then, select Void or Delete.

Furthermore, you may encounter ending balance issues when reconciling your accounts. You can follow this guide on how to fix it: Fix issues at the end of reconciliation.

The Community is always ready to help if you need further assistance in voiding your past transactions. Have a great day.