Torezu

Try the .jar. Avoid saying you're stupid here. People will notice and comment. Rather consider yourself uninformed. Learn to inform yourself, and your residence here will be of a higher quality.

1) Don't sign your posts. 2) Get a better server. 3) If the server itself is running fine, get a better internet connection. 4) Reduce the number of plugins, and ban some items that like cause server-side lag (ComputerCraft, maybe quarries, etc.)

No. More information, and perhaps a bug report, might allow us to "fix it," but for now you're not giving enough to go on. Launcher/pack version, OS and Java versions (and whether 32- or 64-bit), antivirus, a slightly better description of the problem, and a launcher log are a minimum. See the Bug Boards for details.

Somebody probably used "/reload" on the server. Don't do that - it messes up crafting, and now it needs restarted to fix it.

Yeah, odds are that's an AV/firewall blocking the launcher. That's basically the only time I've seen that error.

Go...you know what? I'm not even going to bother trying to help. This bug report is the absolute worst I've seen, ever, since the bug report format started being forced. Try again.

Run the .jar with a batch file that has "pause" for a second line so you can see the error. I'm guessing you need to add Java to your system path, but...

This is one of two things, almost guaranteed: 1) Your AV/firewall blocking your downloads. 2) The minecraft.net servers not letting you connect (more likely, since it shows up with an option for Offline Mode). So, what AV are you using? If it's 2), you're just going to have to be patient, as everyone is experiencing these problems.

Are you certain you have Java installed, then? And yes, the system path addition is the simplest option.

Then use Pastebin like a smart internetter.

Go...look...in the YogBox Bug Board. It's at the top. Oh, and why on this green planet would you use AVG and Avast!? Also, you might want to update your Java at some point.

Try installing OptiFine. If you're playing Technic 7, it's not in there yet.

That's because you didn't click the Submit a Bug Report button.

I'm guessing it has something to do with your ancient version of Java. Go into Control Panel > Programs and Features and remove all versions of Java 6 and Java 7 before u5, and install u5 (64-bit if appropriate). Then try again.

Okay, so what do you actually have for an antivirus? I'm betting that copy of your problem description isn't it.

This is minecraft.net servers being blasted for some reason, and you'll probably just have to wait it out. Keep opening the launcher until it connects.

Antivirus? This looks like a blocked download problem.

So, now you need to post a log to see what might have happened. I would also make sure Avira is updated, as that was causing problems until a recent update.

Did you look around a little? At, say, the Bug Board, and the stickied thread at the top?

I'd have put this in the Tekkit Bug Board, personally. Anyway, to start with, you need a recommended build to join a Tekkit server. Then, to troubleshoot, we really need a launcher log - drop the whole thing onto pastebin if it won't fit in here.

Did you upgrade to 7.1.0? That would have removed EE and thus the dark matter blocks, and made it hazardous for your game's stability to touch them.

EE isn't in 7.1.0, nor is Zeppelin, I don't think. If your mods are working but you're still getting a [sEVERE], you may have an MD5 (authentication) mismatch or something odd. I wouldn't worry about it as long as everything is running normally.

It seems highly likely that you have an AV or firewall blocking your downloads. Which, if any, of either are you using?

Okay, then start putting up version numbers of stuff. "Latest" isn't a version number. You should be using Java 7u5, to match your OS for 32- or 64-bit, and launcher version 1.0.1.3. You also may have an antivirus causing problems, or your download may have been corrupted and you need to get a new launcher.

Yeah, get rid of 7u3 and install 7u5. Also, try wiping and reinstalling Minecraft itself (1.2.5) - sometimes that folder gets junk in it from a previous install.