We have our accounts on one computer and one dedicated email (using Thunderbird) which sends our invoices to our customers in PDF format as an attachment to an email. This stopped working a few days ago. The tech department of our accounts package supplied by Benchmak/Snip has looked at our system and the only thing they can suggest is that the emails are being blocked because may be Thunderbird thinks they are SPAM. We have been using this system for a couple of years now and has been fine. We can send and receive emails to/from this account, it's only the PDF attachments of invoices which isn't working. Can any one help please, thank you.