you for reaching out on the community and telling us about your issue. I do apologize for the issue you're having. That is odd as I haven't seen that error before actually. I think to start off here lets try to copy and validate your file. This will give us a baseline to work with on why you're getting this error. Another thing is this only when you downloads transactions and are you getting it consistently?
I'll leave instructions down below on how to do a copy and validate. It'll be the fourth step in the article.
https://www.quicken.com/support/advanced-data-file-troubleshooting-correct-problems-quicken-windowsOnce you've done this let us know if you get the same error when trying a one step update. Depending what happens we'll see what we can try next!
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