Hi
I had this very same error code.
I phoned sony ps3 and they gave me a new DNS code
I was told by sony that my internet provider as changed its DNS code.
If your PC works but not your PS3, this is your problem.
good luck hope this helps
BLADEs56, June 2009
check this out it may help DNS error 80710102 resolved - PLAYSTATION® Network - PlayStation
type this into google the guys on this site will help you..