Recurring profile - 'Unable to send invoice'

Recurring profile - 'Unable to send invoice'

I'm currently using a heavily customised invoice template which is working flawlessly for all my normal invoices. However it seems that it's failing with any invoices created via any recurring profile.

Upon a recurring profile firing on its specified date, I receive email(s) stating that:


We were not able to replace some of the placeholders in the invoice/email template for invoice# INV-xxxx dated 18 July 2008. Hence it has not been sent to the customer.



I've gone through my template several times and compared all the fields with the fields in zoho default templates and I cannot pick out any abnormalities. And it's even more complicated especially considering the template works fine for normal invoices :)

Is there any way for zoho to provide a more detailed error message, specifically which placeholders couldn't be replaced and/or what went wrong? Any other advice would be greatly appreciated :)

Cheers,
Bernie