For a while I had disabled comments on my blog posts (http://davefagg.com.au/blog) but now wish to enable them.
I’ve enabled the comments facility for new posts, but even though I’ve enabled comments on each individual old post, I can’t seem to make a comment.
You will have to open each post that was published while the comments were turned off globally and turn comments back on.
You can do this more quickly by going to post > edit, finding the posts with the comments off, clicking the checkbox to the left of the name on each, then go to the “bulk actions” pulldown, select “edit” and then click “apply”. In the window that opens, select “allow comments” from the comment status pulldown and then click the update button. You might have to perform this on multiple pages if you have a lot of posts that were published while comments were turned off globally.