Me and some other people on Feanturi's server have had this problem, now I don't know if it's me my connection or anything, but about 2-3 months back I was on his server, and suddenly crashed, eversince i was incapable of joining his server, I'm also incapable of retrieving crash reports, I checked Modloader.txt and it doesn't show anything about a crash, I tried to take a look at it trough some CMD command, but that doesn't log in to a premium account, and thus I can't go online with it.
I deleted my .minecraft file about 5 times, used McNostalgia to downgrade and reinstall all mods, and tried different versions of Minecraft Forge, and yet, nothing.
Sadly I can't send anyone my .minecraft so they can find out what's wrong with it, or the other way around 
[Support Request][IC2 1.43/Redpower 2pr4][SMP Isseus]
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And you never bothered just asking Feanturi to reset your profile on the server to fix that?
Should do that. -
Well I did asked him to delete my profile, so I'd restart at the spawn (about 2 days ago), he said he'd do it, but still nothing
UPDATE: I am capable of logging on, onthe futurecraft server