I’ve got you covered in logging into QuickBooks Online (QBO), @Sparkmatic. I have the fixes available to rectify the error message so you can get back to business seamlessly.
The error you’ve encountered specifies a technical error in loading the page you’re accessing. In this, I suggest troubleshooting steps that improve the application’s performance and eliminate unusual behaviors.
We can start by clearing your computer’s cache to give your browser a fresh start. Otherwise, we can use other supported browsers for the best QuickBooks experience.
For future reference, you can utilize various financial reports to get a snapshot of your business's financial growth. I also added a resource where you could refer to the complete guidelines for customising it:
I’d encourage you to leave a comment about the outcome of the process taken to ensure that everything works fine. I’m always here to help. Take care!