I have 2 PCs running Win7 SP1 and 2 PCs running Win 8.1 with Update. Yesterday both Win7 PCs failed to update (with the 80246002 error). This morning, I tried again. The first Win7 PC failed again so I changed the local DNS setting to 8.8.8.8 and rebooted. WU worked OK I changed the DNS back to automatic and rebooted - WU still worked OK. On the second Win7 PC, I changed nothing and ran WU - it worked OK.
I then ran WU on both Win8.1 PCs with no problems. My router is set to provide OpenDNS settings (208.67.222.222 & 208.67.220.220) so even OpenDNS wouldn't work on the first Win7 PC I tried. I suspect the problem is more complicated than people are suggesting.