Hello NoodleNT,
There would be several reasons for this , as the NIC was changed, is the ip address also changed ?
If not then please do take a look at the following articles : Probably the SBSNsiSignal may have malfunctioned and you may want to restart the services, before that you can take a backup of the SBSStore folder , once you restart the SBS services then the files similar to
initialPXEConfigPath.sbs
2003742225-image.sbs
434234353-client.sbs
Will get regenerated. Please take a look at the articles below :
http://www.symantec.com/docs/TECH127591
http://www.symantec.com/docs/TECH140957
I hope these will help.