I am having issues uploading a CSV file with older transactions. Any idea how I can get around this? It says "Error Importing (Probably our fault)"

Hi there, fionarenniephoto.

I can share some information to ensure your CSV file is imported successfully into QuickBooks Online.

The error you receive could be a result of an error in the file format of the CSV that you're trying to import. With that, we can check if the necessary fields are included to make sure your file is uploaded successfully. You can use this article as a reference: Format CSV files in Excel to get bank transactions into QuickBooks Online. 

If the details and format of the file are correct but the issue persists, we can perform troubleshooting steps to check and fix any underlying browser issues. One of the possible reasons you might be having is that your browser saves outdated and corrupted cache files from websites you visit over time. This can occasionally cause issues with loading or navigating those pages.

We'll start by accessing your QuickBooks Online account through a private/incognito window. Depending on your browser, use the keyboard shortcut below to open one:
 

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

If you're able to see and access vendor transactions, you can go back to your regular browser and clear its cache. This procedure will remove any outdated or corrupted internet files that may be causing issues while browsing.

Alternatively, you can look and use other supported browsers for the best experience while working in QuickBooks Online.

Feel free to reach the Community or leave a comment in this thread for any follow-up questions. I'll be happy to assist. Have a great day!