Windows Update flags an optional update: Definition Update for Microsoft Security Essentials - KB2310138 (Definition 1.129.991.0) but when I try to install it, I get Error Code 80070666.
I've done the full Install the latest Microsoft Security Essentials definition updates
thing (downloaded mpam-fe.exe and nis_full.exe then run both as Administrator). WU still says I need KB2310138.
If I try to update in MSE, I get "Security Essentials couldn't complete .... because of an Internet or network connectivity problem." well I'm online now aren't I?