XF 1.5 User showing messages count as 0 suddenly?

[andrewkm]

One of my users who has 100s of posts is suddenly showing a messages count of 0 on his profile.
How do I go about fixing this and rebuilding that information?

 

[andrewkm]

This fixed my problem:
https://xenforo.com/community/resources/post-count-rebuild.2463/

Curious if this is in core xenforo or if I had to run this?