How to locate  Authorize.net Login ID and Transaction Key

1. Click Account from the main toolbar.
2. Click Settings in the main left-side menu.
3. Click API Credentials & Keys.
4. Enter your Secret Answer.
5. Select New Transaction Key. …
6. Click Submit to continue.

*Please note if your transaction key is already being used by another system, please obtain the key from there and do not create a new one*