Best Way to Send 5,000 Emails?
I run a legitimate website and have about 5,000 members that I would like to send a one-time site update email to. All of my members created their own accounts on my site, and the email will contain legit, relevant site info and an opt-out link, so this is NOT spamming.
What is the best way to get this accomplished? I need to get it done within the next day or two. Detailed advice is appreciated!