SI can support only a maximum of 100 Billers, 100 Customers and 100 Invoice preferences. This is due to an unintended JS Validation restriction occurring in the following files:- consulting.php itemised.php total.php The above files are located in the folder /modules/invoices/ The offending lines are:- jsTextValidation("biller_id","Biller Name",1,100); jsTextValidation("customer_id","Customer Name",1,100); . . . jsPreferenceValidation("select_preferences","Invoice Preference",1,100); Validation is done in include/validation.php file. The workaround is possibly to make the 100 as 10000 or bigger!