https://www.infopathdev.com:443/forums/46.aspx For questions concerning issues in the integration of SharePoint and Microsoft InfoPath.enCommunityServer 2007 SP3 (Build: 31118.962)https://www.infopathdev.com:443/forums/thread/74257.aspxThu, 19 Jan 2012 17:05:20 GMT033a2e2d-04e2-4a9d-be01-a4634161eefd:74257Anson Hidajat0https://www.infopathdev.com:443/forums/thread/74257.aspxhttps://www.infopathdev.com:443/forums/commentrss.aspx?SectionID=46&PostID=74257<p>At submit time, you can have rules fire so that it does a check against your list to see if there is an existing invoice number.&nbsp; You&#39;ll need a secondary data connection to the list and then do a query on the invoice number to see if it returns any results.</p><p>Another option is that&nbsp;you could also create the invoice number on submit to ensure that it will always succeed.</p>https://www.infopathdev.com:443/forums/thread/74242.aspxThu, 19 Jan 2012 14:48:37 GMT033a2e2d-04e2-4a9d-be01-a4634161eefd:74242Don Thie0https://www.infopathdev.com:443/forums/thread/74242.aspxhttps://www.infopathdev.com:443/forums/commentrss.aspx?SectionID=46&PostID=74242I have a shipping form that is used for international shipping.&nbsp; When the form opens it autofills the shipping invoice number by adding 1 to the last invoice number in a SharePoint list.&nbsp; The problem is that if multiple copies of the form are open at the same time they all get submitted with the same invoice number.&nbsp; Is there a way to verify on the initial submission of the form that the invoice number is a valid number based on the list?