installing SQL Server 2008 on Server-Client workgroup

i've been trying to install NetCHK Protect 7.2 (without success) on our
Local Area Network(LAN). I successfully installed it on the Server, which is
a window XP (SP3) operating system, but the workstations are not installing
due to authentication issues.

I suspect i'm experiencing this problem due to the fact that we dont have a
Domain Controller(DC), on our LAN(i.e we use a WORKGROUP, instead of a
Domain). Could this be the source of our problem?

Thank you for your help in anticipation!