Protecting a shared worksheet on a network
 

I have a single page workbook that is shared by 5 people. Two people have to
be able to view it but not modify and the other three have to be able to
modify in all ways; all users need to have it open all day. The answer would
seem obvious, for I have tried following the directions on the help menu, but
I'm not offered some of the steps that are necessary (they are grayed out).
In the "Allow Users to Edit Ranges" dialog box, I try to set permissions, but
it doesn't recognize any other user except for the computer I am on at the
time- I can't access the network or see any other users. The worksheet is
housed on the main server with the 5 people all having access. I can't give
permissions to users it can't find.

I have unshared, unprotected, started over, etc. I even gave up on
individual user access and was just going to protect the whole thing from
modification, but then it required a password to open/view it (even though I
left that blank) and then anyone could change it.

What am I missing? Is it not possible to share a worksheet, yet protect it
too? Is the network a problem?

We are working in Windows XP and Excel 2002