I'm assuming here that you're running in an Exchange environment.

The information on the scheduling tab comes from two places. f you have the
Show Calendar Details option checked then that comes direct from the other
person's calendar, the free/busy hatching is another story...

Free/busy information is published on a schedule (defined in Tools Options
[Preferences] Calendar Options Free/Busy Options) into a hidden public
folder.

If it's just the free/busy hatching that doesn't work, first figure out if
it happens 1) for one user's availability information regardless of who looks
at it 2) from some users looking at this person's information or 3) for some
users looking at various other users' information.

If it's 1 then for the user whose free/busy details don't show (not the
person who can't see them), run Outlook with the /cleanfreebusy switch, and
wait a while* for everything to sync up before testing again. If you need to
know what a switch is and how to use it, look up "switches" in Outlook online
help.

If it's 2 or 3 then you need to speak to your Exchange administrator and get
them to check out the permissions and/or replication on the Free/Busy hidden
public folder.

*how long depends on the user's free/busy sync schedule, whether you have
more than one public folder server, and if so the replication schedule
between them.

Sorry for the long answer, but it's not a quick thing to troubleshoot!

--
TechieBird
http://bwain-dump.blogspot.com