Is there an upper limit on the number of attachments one can send in a single e-mail message? I am coding an application to act as an e-mail forwarding service which receives delivery requests and stores them in a database for later dispatching, and it would come in very handy if I knew beforehand that sending more than, say, 32 attachments is not supported by the e-mail protocols. Is there any such limit?
As @AndrejaKo identifies rfc5321 states there should be no limit to the number of attachments in theory but implementations may vary as @HaydnWVN points out. More likely to hit the limit for the email size (e.g. Virgin Media will return emails larger than 20MB and GMail limit is 25MB)