Connect with and learn from others in the QuickBooks Community.
I'll help you fix the error, tarang.
When you're getting an error 378, it means that QuickBooks is unable to access your bank account using the financial institution's login information.
You'll want to authorized the connection between QuickBooks and the bank by following these steps:
I'm also adding this article for more information: What to do if you see a bank error or bank transactions won’t download.
Please keep me posted if you have additional questions about QuickBooks Online Banking. I'll be here to help you again.