But in a test email, Hubspot adds a string to the end that creates an error so it won't load. Is there a way to override this so the URL can load properly?
Under Settings > Marketing > Email > Tracking, you can choose to not add source tracking tacks and to disable the identity tracking. I'd recommend trying that and testing again.
Thanks for the suggestions. Unfortunately, neither of these have worked and are still resulting in a load error. I have a feeling the issue is on the domain side but it's unfortunate I can't send this email out of Hubspot. Open to any other suggestions you may have.