Ugdhar

What launcher are you using?

Any mod you did not download from curseforge, you should delete and go redownload from curseforge. If you forget which ones, honestly I'd go do all of them.

If you know which mod it is, you should be able to just delete it from your mods folder. I would also make sure all mods downloaded from sketchy websites have been removed, who knows what's been packed into them or how out of date they are.

Post new logs for the new crash please

I don't think you're supposed to run optifine on a server (not 100% sure, but it seems wrong), if you remove it does it still happen?

And you are also still using a lot of mods that came from a bad website. The filenames give it away. Strongly urge you to delete them and redownload them from a legit site. Others will likely suggest the same.

Where did you download your mods from? You should only download from curseforge or the developers website, not sites like 9minecraft. Check out https://stopmodreposts.org/ for more information. If you downloaded them from anywhere else, I would delete them, and redownload them from curseforge.

if you add a line that says pause at the end of your bat file that starts the server (I assume you're using a batch file to start it), it will wait for a keypress before the screen closes to help see what's going on. Also, post your server log to a github gist or pastebin or something, and link it here, it will also help in figuring out what's wrong.

To expand upon this, make sure you at least skim through the description of the mod on CurseForge, just in case the mod you want says it requires another mod, you'll want to make sure you download any dependencies required. i.e. RFtools requires McJtyLib, so if you wanted RFTools, you would also have to make sure and download McJtyLib.

It looks like you may have 2 versions of the same mod in your mods folder. Make sure when you update a mod, that you remove the old one after putting the new one in there. Also, make sure you are downloading mods from curseforge or the developers websites, other websites like 9 minecraft and stuff are bad, check out https://stopmodreposts.org/ for more information on which sites to avoid if you are unsure.

Get ahold of the server logs for a period of time that the problems are happening, and post them to github/pastebin or something, and post the link here.

So just a heads up, you should not repost .jar files for mods that you did not write. Simply giving us the names of them would have been sufficient. In order to update those mods, you would have to first see if the mod author(s) will/have updated them. If not, and/or they have no intention of doing so, you would then need to ask permission to update their code to 1.12.2. Depending on how they have their original sources setup, this may or may not be required, but is a good practice regardless. And of course, you will need to know Java fairly well, and be at least somewhat comfortable coding forge mods in order to update these mods, considering how much has changed from 1.7.10 - 1.12.2. If you were looking for a simple answer, (i.e. you are not a programmer) the simple answer is: you can't.

TBH most of the tutorials I've seen are crap, and/or just a "here, type this to make this thing", and then copy paste code. Most tutorial writers run out of steam once they've covered the simple things every tutorial writer covers, so they're mostly all the same anyway, video tutorials being the worst IMO. If you know Java (I'm assuming you do), just setup a workspace (the forge docs for 1.12 work for this), and start tinkering. Looking at the vanilla code is a good resource, and you can always find open source projects on github (quality may vary). When you run into issues, just make sure you have a working github repo of your project, and post logs and as much detail about your issue as possible when looking for help. Make sure to include what you are trying to accomplish as an end result, that can often help people give you a better (or the right) way of doing things. And of course, if you do not know Java, learn Java first, because you will have difficulties otherwise, and the people on these forums are not keen on teaching people Java (don't blame them).

First, you should make your own thread for your problem, and post logs to give more detail into what is going on. Secondly, this post is 3+ weeks old, for an old version of forge for 1.14.4, there have been many updates since then, so if you're still using .11, then update!

It sounds like you may have broken your .jar file association. I believe there's a tool called jarfix (search google) that will re-associate them with java.

Did you scroll all the way to the bottom of the version list? Sounds silly to ask, but just making sure!

Still there. After you try it, scan through the log to see if it mentions Optifine, if it's still there, then it's not gone.

You added Optifine for 1.12.2, but did not remove the one for 1.8.9

Since you're using Minecraft 1.12.2, I would say most definitely. If it still crashes, post the new logs.

You should post full logs, it should give a little more detail about what's going on.

Are you using Optifine? If so, try removing it. I searched the forums for "java.lang.NoClassDefFoundError: bnk" and that was one of the suggestions I saw.

You need to use java 8 for 1.12.2, java -version should show which version you're running.

I believe there is an optifine for 1.14.4, but it is not compatible with forge, it does its own thing to add itself to Minecraft.

Please give details on how you are starting the server, as well as posting logs.