Microsoft certificates and ssl

Hi,
I have configured website in iis 5.1 in windows xp pro. sp1 machine. I posted the server request certificate to CA which exists in windows 2003 server sp1 machine.
I got the certificate back from CA and installed to xp machine named mac6 which has IE7. I can able to access the url like https:\\mac6\default.aspx from mac6.
If i try to access from somother xp machine the same url It says “The page cannot be dusplayed”.
I need to know whether i can use xp machine which contains iis 5.1 and IE7 to provide security to website?.
Do i need to enable client certificate if other than native machine access the same site?.
plese help me out on this.

Thanks in advance.