Integrity constraint violation: 1062 Duplicate entry '2147483647' for key 'tblinvoices.PRIMARY' Errors
Performing an action that creates an invoice (including the daily automation cron tasks or when your staff or a client places an order) you may observe an Oops!
Integrity constraint violation error message.
The full error is:
PDOException: SQLSTATE: Integrity constraint violation: 1062 Duplicate entry '2147483647' for key 'tblinvoices.PRIMARY' in /path/to/whmcs/vendor/illuminate/database/Connection.php:464
The Invoice Starting # setting is an integer value that is larger than
2,147,483,648 (2 billion 100 thousand), which is higher than MySQL® can accommodate.
To assign a custom invoice numbering format, see Configuring a Custom Invoice Number Format.
1. Using a tool like phpMyAdmin, perform the following query against WHMCS's MySQL database and note the result:
SELECT MAX(invoiceid) + 1 FROM tblinvoiceitems;
2. Log in to the WHMCS Admin Area.
3. Go to the Invoices tab at Configuration > System Settings > General Settings.
4. Enter the value that you noted in step 1 for Invoice Starting #.
5. Click Save Changes.
Invoice Starting # will be empty after saving. This is normal.