Hi there, @Lordofthetrees!
We haven't received any reports from other users like you who received error 103 when connecting your bank. I'm here to share a few steps you can follow to get rid of the error message you received.
But first, may I know any name or information of your bank? Any details you can share will be appreciated and can also help me completely resolve your concern.
Nevertheless, you have the option to click the Reconnect button within the error message you received. If it still doesn't fix the error, you'll have to manually update your sign-in information.
In addition, here's an article you can read to learn more about how you can fix the banking error 103: Error 103 for QuickBooks Self-Employed.
Please know that even if the article above is for the US version of QuickBooks Self-Employed, the same steps applies for the UK version.
As always, you can visit our Help Articles page for QuickBooks Self-Employed if in case you need to learn some easy steps for any of your future tasks.
Please let me know in the comment section down below if you have any other questions. I'll be keeping an eye for your response and always ready to help.
