It sounds like you have checked to make sure both accounts involved in the transfer have the “Bank Account” format type. This is a format type that will trigger the Transfer Clearing Account. In addition, make sure you have told the system to use a Transfer Clearing Account in Transaction Activity:

1. Select Enter Transactions to display the Transaction Activity screen.
2. From the Transaction Activity screen, select Tools | Transaction Activity Options.
3. From the Transaction Activity Options screen, select the Transfer Clearing Account button.
4. Highlight your transfer clearing account on the list and select OK.
5. Try to perform a transfer transaction once more.

Verify you have a Transfer Clearing Account in your Chart of Accounts. You can also check the format type of your Transfer Clearing Account to make sure it is blank (none). Also, have you tried running the Test & Correct Utility? You should run all of the tests to ensure your account file is accurate.