I am exporting Transaction Details by Account. Many transactions have blank class data but in the register the class is assigned. How can I export class reliably?

Let's ensure the Class column is enabled on the report so it will be available once you export, Jackie.
 

Before exporting the Transaction Detail by Account report, double-check if the Class column is turned on to display appropriate data. Refer to the instructions below.

For the new reporting interface, click the Columns button, and then tick the designated Box icon for the Class option:

For the old reporting interface, click Customize, select the Rows/Columns dropdown, then locate and enable the Class column. After that, Run report:

However, if you get the same result or the Class option is already enabled but still encountering the issue, let's open your account using a private session. Follow these keyboard shortcut keys to proceed:

• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + N
• Google Chrome: Ctrl + Shift + N
• Safari: Command + Shift + N

If the Class details are visible on the report via incognito mode, revert to your regular browser and clear its cache and cookies. Doing so eliminates excessive data utilities that impact the platform's full functionality. You can also consider using another supported browser once the issue persists.

Alternatively, you can pull up several class reports in QuickBooks depending on your required data. Check out this link for complete guidance: Run reports by class in QuickBooks Online.

Aside from reports, you can also transfer other QuickBooks data to Excel. Once you need to, you can utilize this article to help you through the process: Export your QuickBooks Online data.

We're still available once you have more questions about exporting reports with class details. Just leave a comment below so we can assist you.