"error code 500 connection error" every time I try to set up direct connect banking. what to do?

Thank you for visiting the QuickBooks Community, susanbuhner. Let's go over some troubleshooting procedures to get rid of the 500 error and connection problem you're having so you can set up a direct connection in QuickBooks Desktop smoothly.

Beforehand, make sure you have the following:

• You backup your QuickBooks company file.
• Your computer is connected to the internet.
• You have the latest release of QuickBooks installed.
• You can sign in successfully to your bank’s website.
• Your bank didn’t report a server outage.
• Your account info (like account number and routing number) in QuickBooks is correct.

Then, I recommend ensuring the financial institution's list is up-to-date on your end. Here's how:

1. Go to the File menu at the top and choose Close Company.
2. Press both the Command button and the number 1 on your keyboard to display the Product Information window.
3. Choose the Logging tab, then Delete FiDir.
4. Close and reopen QuickBooks.

After that, open your company file. Then, set up a Direct Connect from there.

If the problem persists, you have to create a new test company in order to resolve online banking issues with QBDT for Mac. You can open this article to see the process: Fix online banking issues in QuickBooks Desktop for Mac. You can continue with the last suggested solution in the article if the issue continues to occur.

Lastly, refer to this article if you need steps on how you can review your bank transactions to avoid double entries: Add and match transactions in QuickBooks Desktop for Mac.

Stay in touch with me if you have additional questions about connecting bank in QBDT for Mac. I'm here to answer them for you, susanbuhner.