My Outlook 2007 was working fine with Gmail, and sending attachments of all kinds... but today, for some reason it's no longer able to send PDF attachments, and it's getting stuck in the Outbox.
I tried clearing the Outbox and moving the email with attachment to Drafts, but it still won't send it. Regular emails and MS Word attachments are going through just fine.
The attachment size is a 4Mb pdf.
I tried upgradeing Norton AV to 2011, did CCleaner... but can't figure out the problem.
What else can I try?