Can't connect with Forge (Schematica) loaded

So I've been working on a facility like project on the server and to make it feel more modern I'm wanting a really sophisticated redstone elevator. One featured on Mumbo Jumbo's channel a few months back would be perfect but there was no world download nor tutorial to go off, so I settled on a design very similar made by ilmango. Problem is however, after installing Shematica on the latest version of 1.12's forge (not 1.12.1) and creating a schematic of the elevator I can't get on the server! It seems whenever I'm running forge and try to join the server I get kicked with a "Internal Exception: java.io.IOException: An existing connection was forcibly closed by the remote host" error. Can someone help me out please? I would really like to continue on with my facility and start with the underground segments.
Thanks
-Cleric

Looking from the exception, my guess is that there is some plugin trying to stop modded clients from getting on the server. Have you had this issue before?

I don't believe so no. That is a reasonable explanation though, so how can I get in with Schematica then?

Try again, currently updating craftbukkit. Its late and I dont have time to test it though.

I remember someone having this issue, but dont remember how to fix it.. I always play with forge, I havent had any issues

Wait do you have any other mods loaded than schematica?

I also have Optifine C4, and BetterFPS loaded up in addition. I also tried joining with the Shoulder Surfing mod a while back which didn't work also. I'll give it another try sometime today to see if it works. If it doesn't I'll let you know.
Thanks guys

- - - - - - - - - -

Guess I won't find out until they update Schematica now xD

I've just tried to load in again with Schematica for 1.12.1 and Optifine C5, still kicked with the same error

Try to connect with only forge and no mods installed?
If it still throws that error then I have no clue what's up.

Alright turns out it's Optifine for some reason. With Schematica loaded but Optifine not I managed to connect. Also with just Optifine and Forge I couldn't connect, but just Optifine I can. Weird

Ohh. Have you chehked if the optifine version you use is usable with the forge you use?
Normally you take the latest forge and roll with it, but with optifine, before you download it, click changelog of the version you are about to download and check the required forge version from it. Then manually download that specific forge version. Hope that helps

Alright it's all working now. I don't know why but it's just kinda decided it's going to work so that's good. I can finally build that elevator now :D

I also have Optifine C4, and BetterFPS loaded up in addition. I also tried joining with the Shoulder Surfing mod a while back which didn't work also. I'll give it another try sometime today to see if it works. If it doesn't I'll let you know.

I don't believe so no. That is a reasonable explanation though, so how can I get in with Schematica then?

Looking from the exception, my guess is that there is some plugin trying to stop modded clients from getting on the server. Have you had this issue before?

I remember someone having this issue, but dont remember how to fix it.. I always play with forge, I havent had any issues

I don't believe so no. That is a reasonable explanation though, so how can I get in with Schematica then?

Looking from the exception, my guess is that there is some plugin trying to stop modded clients from getting on the server. Have you had this issue before?

Looking from the exception, my guess is that there is some plugin trying to stop modded clients from getting on the server. Have you had this issue before?

Looking from the exception, my guess is that there is some plugin trying to stop modded clients from getting on the server. Have you had this issue before?

I don't believe so no. That is a reasonable explanation though, so how can I get in with Schematica then?