I am using the latest version of All The Mods
I am using Java 1.8.0_131
I am also using OptiFine_1.12.2_HD_U_D1

https://pastebin.com/nR0190Ft

First of all... please DO NOT post Crashlogs like that.
Upload them to Pastebin.
Secondly, remove added mods and update to latest Java. Both of you are using outdated versions.

What's the latest version? Is it not v5.9.2?

That is the latest version of modpack yes. I was talking about your java. They are both out of date. The latest is 161.

For me too everytime i try to join my server
I am using ATM3 v5.9.2 and added architecturecraft 1.12.2-2.68.
My installed java version is 1.8.0_151-b12
Crashlog: https://pastebin.com/mK0JX62X

So i updatet my java and told minecraft to use the latest version and removed the added mod just like you suggested. It still crashs.

Here is the crashlog: https://pastebin.com/MR3T2DHR

(Also my friends game is crashing too everytime (we are playing on the same server))

I also updated my java and reinstalled All The Mods just in case. I ran it without optifine, which ran fine until the game started lagging horribly (a side effect of my old computer), so I ran the game with optifine, and it crashed once more:

https://pastebin.com/bZMccVuv

Is there any way to run the game with optifine without the game crashing, or is it impossible?

Edit: I removed the tessellating cable from the world without optifine, and I went back into the game with optifine, and the game functioned normally.

The cables involved in the crash corrupted and assumed a peculiar texture.

https://imgur.com/a/3DYVG

Please tell me if you need more information. I know you labeled this as non-reproducible, but you guys might benefit from analyzing bugs.

Thanks

SpongeGuy you are still using java 1.8.0_25.
If you installed the newest java version you have to tell minecraft to use it.
To do this open the twitch launcher and go to settings->minecraft. Then on starting method choose Jar Launcher and the newest java version. Now when you launch the game it will use your newest java install. Maybe that will fix you problem.

Thanks, Trostan.
I made sure Minecraft ran the latest version of java and the cables reverted back to normal.
Hopefully I don't run into anymore problems

Glad to hear. My Problem was solved by installing the latest Optifine. I removed the block that caused the crash as soon as i got ingame (a flat Transfer node) and i hope too i doesn't get crashes anymore