Troubleshooting Invoices

If you encounter errors or issues while working with or customizing invoices, see the sections below to start troubleshooting and resolve the issue.

For more information, see Billing Logic.

Generating Invoices

For more information, see Invoice Configuration.

You may encounter the following common issues:

Error or IssueExplanationNext Steps
The system did not generate one or more invoices.This issue may be due to an issue in the service or domain configuration, a previous invoice, or a problem with the system cron.Missing Service Invoices
Missing Domain Renewal Invoices
The system generated two invoices for the same service.This issue may be due to the system cron running twice at the same time or there may be an issue with the service’s Next Due Date value.Duplicate Invoices (Different Dates)
Duplicate Invoices (Same Dates)
One or more invoices does not include tax correctly.This issue may be due to a problem in your tax configuration settings or due to a setting in the client’s profile.Invoices Are Missing Tax
The system cancelled a domain renewal invoice unexpectedly.This issue is due to your domain redemption or domain renewal settings.Cancelled Domain Renewal Invoices
A service’s Next Due Date value has moved to a date several months or years in the future, resulting in some invoices not being generated.The system has registered multiple payments for the service.Unexpected Next Due Date
Maximum execution time exceededDuring invoice generation, this error may be due to a high-resolution logo image in the PDF file.TCPDF Timeouts
Oops! PDOException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '2147483647' for key 'tblinvoices.PRIMARY' in /path/to/whmcs/vendor/illuminate/database/Connection.php:464The Invoice Starting # setting is higher than MySQL® can accommodate.Duplicate tblinvoices Errors

Viewing or Using Invoices

For more information, see Invoice Management.

You may encounter the following common issues:

Error or IssueExplanationNext Steps
Client details on an invoice do not match their profile.This issue may be due to your invoice settings or the presence of a billing contact.Unexpected Invoice Details
The system generated a blank invoice.This issue may be due to the system cron running twice at the same time.Duplicate Invoices Same Dates
Characters in a PDF invoice or quote appear as question marks.This issue indicates that your selected font does not support the displayed characters.Question Marks in PDF Invoices
The system logs the client out while downloading an invoice.An issue with pdo_mysql clients on some CloudLinux™ servers is causing unexpected behavior.Logout During Invoice Download
Oops! Error: Module Not FoundThis error indicates that you have activated and configured the payment gateway, but the corresponding file is missing from the /modules/gateways/ directory.Oops Module Not Found Errors
TCPDF ERROR: [Image] Unable to get the size of the imageThis error indicates that your server cannot use the cURL library function to load the logo image for inclusion in the PDF invoice.TCPDF Image Size Errors

Sending Payment Reminders

For more information, see Configure Payment Reminders.

You may encounter the following common issues:

Error or IssueExplanationNext Steps
The system generated an invoice but did not send the associated payment reminder.This issue may be due to an issue in the client’s settings, a missing email template, or a problem with the system cron.Missing Payment Reminders

Last modified: June 5, 2024