Here is the solution of Quickbooks error 5511:
Open Quickbooks business file.
Click edit and after that click on Preferences.
Choose Integrated Apps.
Click Company preferences for verifying check-mark in addition to the Quickbooks Sync Manager or not.
In the event that sync manager is not marked, just mark it. You have to do it when the company file is opened.
Make sure you have the latest update from the QuickBooks Sync Manager.
The steps given will help you to solve this QuickBooks error. Else, you can dial QuickBooks Customer Service Number 1-800-986-4607.
