If you are using Goodbudgets with the Accounts feature turned off and then activate the Accounts feature, a transaction named “Activate Accounts – Adjust Unallocated” will be created in your household.
This transaction is a necessary transaction that makes sure that the balance you have in your Account(s) matches the amount you have available to budget with in your Envelopes. Because it is serving this essential function of keeping those balances consistent, it cannot be edited or deleted.