Sounds like your workbook is not shared.
Tools>Share Workbook

"Will" wrote:

> Ok . . . But how do I use it? When? The buttons remain "grayed out" on my
> toolbar. I can't find anything about these buttons on the internet or on
> Microsoft Office Online.
>
> Thanks for your reply Gary.
>
> "Gary L Brown" wrote:
>
> > I believe they are used for keeping track of versions of a workbook and
> > identification of the user.
> > HTH,
> > --
> > Gary Brown
> > gary_brown@ge_NOSPAM.com
> > If this post was helpful, please click the ''Yes'' button next to ''Was this
> > Post Helpfull to you?''.
> >
> >
> > "Will" wrote:
> >
> > > What is the Check In and Check Out command buttons used for?