Did you originally import your customer information from a file of some type?
Is this the Invoices starter solution released with FileMaker 12 or the one released with FileMaker 11?
Yes, I imported my customer information from a excel spreadsheet. I matched the fields as it pertained for my set-up.
I am using the FileMaker 12 starter solution.
When you imported, did you enable auto-entry options? If you did not, your imported records lack a needed serial number to match to records in the invoices table.
See this thread for a detailed description and how to fix this issue: Help importing Excel data into a Filemaker Starter solution
Phil, Thanks for your help. That was the issue.