Why isn't the Membership plugin sending out all of the emails I set up?

I have two emails set up in the communication section of the membership plugin. One is for when the user first registers and they're pending approval, and the other is for when they are approved. The first email isn't sending out, but the second email is. The only "solutions" I've come across are upgrading (which I've done, and it's still not working) and one solution saying to download an interim fix, but the link was broken, so I couldn't download it.