I am working on a website (hosted by GoDaddy) where the core of its functionality relies on time-critical e-mails being sent out to large numbers of subscribers (starting at thousands, planning for expansion beyond that). By time-critical, I mean within 20 seconds (max) of submission, or more preferably within 5 seconds or so. I have worked through a number of solutions to try and make this work, but had problems:
- Sending mails individually is far, far too slow, even in a seperate thread (I am using ASP .NET), and using GMail SMTP it eventually failed after sending about 90-something e-mails.
- Sending mails in bulk, ie. as one long BCC list, always has problems due to recipient list length limits. I have tried this with both GoDaddy and GMail. Both place a limit of 100 recipients per message, and GoDaddy mail accounts have max. 250 relays per day
I then moved to asynchronous mail sends, but almost immediately this got me blocked from using GMail SMTP for a day. I have worked out a system to cycle through the GoDaddy’s available email addresses, as i have 500 addresses with 250 relays per day each, which would mean 125,000 mails a day. If i were to send 25 bulk e-mails a day that would mean a maximum of 5000 registered users on the site. This solution works with async sends but the user limit is quite low, not to mention its an unprofessional and unreliable method of solving the problem, and I have to setup all addresses manually (all 500 of them!), and i’m therefore not happy using it.
I’ve also looked at all sorts of SMTP services from other providers, but none seem to offer the lack of limitations in rate of sending/async sends/relays per day that i need, as they all have to protect themselves from spammers. They also all seems to be ridiculously expensive. So i’m considering setting up an SMTP server of my own.
My question is this - does anyone know of any other way to solve my problem without a custom server? Or of any way of coding batches of e-mails in ASP .NET so that they are sent very quickly without overloading the server?
Also, I don’t know much about dedicated hosting…but from what I understand I have pretty much full control over the server if I buy that. Does that mean I can, for example, pay for dedicated hosting on GoDaddy, then install my own SMTP server software on it without limitations? Or if not GoDaddy, would anyone else let me do this? Or is setting up my own server the only option?