This error usually occurs when the customer-related data available in the Webgility Software database is different from what you have in Quickbooks in other words we can say that the recent changes made to the customer data in Quickbooks have not been updated in the Webgility Software database this results in an invalid reference error due to data mismatch.
Error Message
There is an invalid reference to Quickbooks customer.
Troubleshooting
Method 1
1). From your Webgility Desktop Software navigate go to Integrations> Get latest data and settings> Download Quickbooks Data and Settings> Download data.
2). Once done then try to post the order again.
Method 2
1). From your Webgility Desktop Software navigate to Integrations> Get latest data and settings> Download Quickbooks Data and Settings> select Re-Download All Data.
2). Webgility will ask for your confirmation with a notification popup as shown below so you will need to click on Yes and wait for the process to complete.
3). Once done then try to post the order again.
Method 3
1). From your Webgility Desktop Software navigate to Integrations> Stores> Advance Settings> Application tab> Quickbooks Settings select Clear last download date for Quickbooks items then select Save & Close.
2). Now navigate to Integrations> Get latest data and settings> Download Quickbooks Data and Settings then select Download Data> click on Download data.
3). Once done then try to post the order again.
If the issue still persists, please feel free to contact Webgility Support.