I find when summoning, if I run to the sign as soon as it appears it works more often then if i let them linger and I choose who I want. Which makes me think that the "failed" attempts are just people that have been summoned already and I was too slow.
But for getting summoned it is rare for me, and the few times It did work it was a bit laggy.
If you're summoning people, stand on top of they're sign after the initial press. When it says you can summon them again do it quickly. That usually works for me. Being summoned on the other hand... Wait a while.
i have been having summoning difficulties also. keep getting fail fail fail, my computer specs and internet/router are all top notch too. i have been invading in anor londo lots too and on most invasions the host is alone attempting to summon, or they just go summon solaire?? i have fought him more than anyone.
Well first there's the issue where people need to have their NAT and UPnP or something both open and available in their GFWL settings.
Then there's the fact that most of the time, summon signs can be around thirty to a full minute old. And it's possible that by the time you see it, the phantom has either been summoned by someone else or they removed their sign.
Whenever I get a summoning failed, I assume it's because either the phantom didn't set up his GFWL as I mentioned a moment ago. Or the sign is outdated. I just have to keep trying but remember who didn't work and only try them again if I do a full cycle.