ContributionsMost RecentMost LikesSolutionsRe: Customer unable to open invoices - Red diagonal line Thank you for the reply. I have tried using various different web browsers and the issue remains unsolved. What web browser do you recommend? I have also tried using the MYOB iPhone invoicing app with no luck the red diagonal line still appears across the customers screen. The only way I am currently able to send invoices without this issue is to download the PDF invoice to my computer and then attached to an email, this is super frustrating and time consuming. Customer unable to open invoices - Red diagonal line Hi Mutiple customers per day are unable to open our invoices. This has been going on for months. I have included an image of what our customers are receiving.