QuickBooks point of sale error code 140305 and looking for a valid fix to it? Well, if your answer is yes, then your search ends over here. Today’s article is entirely based on the information related to the QuickBooks error code 140305. The error code is usually seen when the user runs a financial exchange in QuickBooks desktop point of sale. This error rolls in with an error message stating as “Error 140305: You have reached the maximum allowed number of customers in QuickBooks”.