QuickBooks error 9999 is an online script error that users often face while trying to download their bank transactions or feeds in QuickBooks Online. An error message stating, “Sorry, we can’t update your account. There are numerous reasons that can cause it, such as interruption to the connection between QuickBooks Online and the bank or failure of the web browser to load the bank website because of the cache files and cookies stored in it. If you’re one among the users facing QuickBooks online banking error 9999 and want troubleshooting assistance to fix it, contact QuickBooks professionals at 1.855.738.2784.