QuickBooks Online sync error: Error validating Email Address: Please provide multiple email addresses as a comma separated string.
Why the sync error occurs
This error occurs when a vendor in Key CashFlow is trying to sync to QuickBooks Online, but there are no commas to separate multiple email addresses in the email field.
How to fix the sync error
Enter commas to separate multiple email addresses in Key CashFlow, or delete all but one email address, and sync again.