AetherPirate

See if this issue is affecting you: Otherwise, pastebin a log

pastebin a log, attachments do not work. Aether does not work prior to coffee

pastebin a log, and check if this issue is affecting you:

Both of you, see if this issue is affecting you

Where did you get that launcher from? download a new one from http://www.technicpack.net/download after that, we can look at your other issues

go to C:\Users\**YourWindowsUserName**\AppData\Roaming\\.technic\modpacks\tekkitmain\mods and remove the older simplyjetpacks jar file, and paste the new one in. Then re-launch tekkit

try any browser other than Edge

Your antivirus might be blocking the download, try disabling If you are using Edge, get any other browser and try that too.

odd, works for me try https://minecraft.curseforge.com/projects/simply-jetpacks/files/2206512/download

This is a known bug with tekkit 1.6.4. The culprit is Simply Jetpacks, you can update with https://minecraft.curseforge.com/projects/simply-jetpacks/files/2206512 Note that if you are playing on a server, the server owner and all clients would need this newer jar file

pastebin a log

Fluiducts are a bottleneck. Attach the tesseract directly to the port.

See if the recent Nvidia update affects you: otherwise, pastebin a log

See if the recent Nvidia update affects you: otherwise, pastebin a log

See if the recent Nvidia update affects you: If not, pastebin a log, attachments do not work here

Your bin, confg, and mods folder need to be zipped up as modpack.zip, You've got those folders inside another folder

pastebin a log. Also see if the recent Nvidia update affects you.

pastebin a log, and also see if you are affected by this recent Nvidia update:

attachments do not work ,use pastebin.

Is the water still being removed from your turbines and sent back to the reactor?

see if this issue applies to you

pastebin a log Is the client running the EXACT same version of tekkit classic as the server?

Allocate less RAM, try 4GB

See if this applies to you

It sounds like you are using a world that was created on a different server that had mods that included those blocks, and now you are trying to launch it with a modpack that does not. Does the server complain of missing items when you launch it? If so, it wants you to type /fml confirm to finish removing them. If this world really was created with a different modpack, you may have other issues.