More likely, there is some issue with your
SimplyMepis network configuration.
Does your new machine have the same
network card as machine this hard drive was in when you installed SimplyMepis? If not, the likely culprit is your network card driver.
Check your bootup messages very carefully, they may point to a driver issue.
What does the output of the `ifconfig -a` command tell you?
You may also find some good advice on the
Mepis Networking Forum.