It’s extremely easy, ask them to register!
Unless your a very large blog like lifehacker.com where you almost need to limit commenting to registered users, DON’T DO IT! You will turn off many many people.
I know I personally won’t comment on a blog that forces me to register. Why should I register? Why do I want to remember another password, especially if I might only comment once? It basically boils down to: “what’s in it for me?”
By adding a small barrier to entry, even just to reduce spam comments, you’ll significantly reduce the odds of people interacting with your blog. You’ll stunt it’s growth. You really have to ask yourself, is it worth it?
Especially if there’s really no reason for it. If because of spam, then you should really think about using this solution. YOU should be the one dealing with the spam, not your commenters. You shouldn’t be pushing this task off to your community. Especially not with all plugins available today like Akismet.
Again, and I repeat this because it’s such a simple thing to avoid, don’t force people to register to your blog to post comments. Actually if you think about, you can’t do this unless you ACTIVELY implement it. It’s not a default setting you just turn off, you need to intentionally spend time to implement this limitation.
Don’t force people to register to your blog to post comments, It’s really going to hamper your abilities to create your online community.
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