How can I set smf show who's online

[tu111]

I use smf 1.1.3 and yabb template.  Now it's show who's online at the bottom of my forum but not update I mean it's show only me online always.  How can I set this feature?

[codenaught]

Try the following to see if it helps:

Admin / Forum Maintenance / Empty out unimportant logs.

Edit: Also if that doesn't help, try changing your theme to the default SMF theme to see if it works there.