10001220 
Message
Enter quantity greater than 0
Diagnosis
From the SAP Business One Main Menu, you have chosen
Inventory 
Item Master Data 
.In the Item Master Data window, you have selected one of the following tabs:
Purchasing Data
Sales Data
You have attempted to enter a quantity of zero or less in one of the following fields:
Items per Purchase Unit
Items per Sales Unit
Procedure
In the Items per Purchase Unit field or the Items per Sales Unit field, enter a quantity greater than zero.