"something's not quite right unexpected token < in JSON at position 0 appears without any indication of what this means. how do I get rid of it and print the invoice?

Hello there, @peter38.

The error message can be caused by a cache issue in your browser. Let's do a few troubleshooting steps to fix this.

Let’s start by opening your QuickBooks Online using a private browser. This will lessen the amount of data collected by websites.

Here are the keyboard shortcuts to access a private browser:

• Google Chrome: Press Ctrl + Shift + N
• Firefox or Internet Explorer: Press Ctrl + Shift + P
• Safari: Press Control + Option + P

If this works, let’s go back to your regular browser and clear the cache to refresh it. However, if you still encounter the same error message, try a supported browser to narrow down the cause of this behavior.

For a reference you can visit this page for tips and resources on managing your account in QuickBooks: Help articles for QuickBooks Online.

Don’t hesitate to drop a comment below. If you need further assistance, I’ll get back to you. Have a good one.