Error: 3180 - There was an error when saving a Invoice. QuickBooks error message: The internals could not be locked. They are in use by another user.
This error can happen if a QB user has a modal dialog box open while the Web Connector is attempting an insert operation such as an Invoice insertion.
A "modal dialog box" is the kind where the QB user interface is requiring the user to Ok/Close the existing box and clicking anywhere else in the QB interface there is an audible "beep".
A classic example of a modal dialog box is the window when the user is Editing an Item. The user must OK to commit their changes or click Cancel to dismiss them - the user cannot click anywhere else in the QB user interface.
When QB is showing a modal dialog box it locks the company file for writes. If the web connector at that moment in time is attempting to insert an invoice this error will happen.
There are other places where QB presents a modal dialog box but Edit Item is a prime example.
Vinosmith can attempt to recover from this error and retry the operation but if the QB user remains in the modal dialog state this error will happen again, up until the maximum retry attempts.
The best strategy is to minimize the time a user is in a modal dialog state in QB as much as possible; while the Web Connector is actively attempting write operations.