here is my experience,hope to help everyone。
my officepc,win7.
my laptop in home,win7.
my homepc,winxp.
all installed with hamachi.
officepc->homepc green.
officepc->laptop in home blue.
laptop and homepc in same subnet,and same network configuration.
this confused me for a long time.
today i solve this problem by turning off the windows firewall in my laptop.
offciepc and homepc have already turned off the windows firewall before today.