Page 45 doesn't seem to exist. Did it get corrupted?

Yeah, like when you click "last page" you see another page number listed and click on that and you're on the previous page number but really still the last page.

Seem to be an issue that's been around for maybe two years.

I've had that problem with that thread on and off for the past week.

That has happened to other threads in the past, too. Does it have to do with mods deleting posts?

As others have said, it's been happening for a long time with other threads. I'll just change the number of "posts per thread" to 40 and you can see the next page.

It happens all the time. A post gets made creating a new page of a thread, but then someone anywhere in the thread deletes one or more posts. The new page still exists because the placeholder was created for it, but there are now no posts in it.

Also, that thread only has 29 pages unless you're on newbie settings.