Need help adding mods

[JerryFrankson]

Hello there!
I've played quite a bit of FTB (mostly Ultimate) but then started looking for different things. I found plenty of mods that are really cool, and that I'd like to add to a pack. However, I've got very little experience (I only added Optifine once, and that was by following a step-by-step tutorial). Every time I try to add something, I get some kind of crash. I'm an absolute noob when it comes to this: I only know you can add them easily through the 'Edit Modpack' button in the launcher and that there'll probably be ID conflicts to change through configs, so if anyone would like to give me some tips on how to successfully troubleshoot why mods aren't working, that would be amazing.

Basically it comes down to this:
How do you know why it isn't working? What log do you need to look at (launcher, MC crash log,...)?
And when that's established, how do you make it work?

I can provide concrete examples if necessary, but rather than getting it fixed, I want to know how to fix it myself in the future.

 

[lavarthan]

The console log provides a lot of info as to why it is crashing. Google is also your friend if you want to find this out yourself. Just search for the error. Try searching for the cause of the error and quote the error log in a few different ways. Not just the first lines of the error in the log, maybe the second or third line maybe even the second or third paragraph of the error.That is how I find the answer to a lot of the errors I see. You will also want to ensure that you have FTB installed in the recommended way by following this guide exactly.

Before you add any mod dump the IDs using NEI from your current working pack. This will give you a list of the IDs that are available for you to use with the new mod. Once you have that try installing the mods one by one. An ID conflict will more than likely read like this, 'Slot xxx is already occupied by xxx' That is not the exact error, but it is close. Now go into the config for the mod you just added, find the name of the item that is listed or the ID which ever is necessary. Some names for items do not correspond exactly to the error. Change the ID to a free one in your list and mark it as used on your list. Try running the pack again. This may take a few tries until you do not experience anymore ID errors. Note RedPower has a different error log for ID errors with it. The exact error begins with:

java.lang.NullPointerException at com.eloraam.redpower.RedPowerControl.setupBlocks(RedPowerControl.java:117) at com.eloraam.redpower.RedPowerControl.load(RedPowerControl.java:50)

For RedPower ID conflicts open the config of the mod you are trying to add and check each ID to see if it is one on your list reserved for RedPower. If it is change it to a different ID that is not being used.

For other errors first check your installation of the mod. Did you install the correct version? Are there any other mods that are required for the version you want to add? Most of the time these are the types of errors you will experience. Finally there is no shame in asking for help.

Edit: BlockIDs and ItemIDs are different so make sure you use the correct one.

 

[JerryFrankson]

Wow, thank you for the information. I didn't expect such an extensive answer so quickly
I assume only the last line/couple of lines of the log is relevant? Also, is the minecraft crash log important?

 

[lavarthan]

The crash log can be important if you do not have a launcher that provides the info as well. The server log can also be important if it is the server and not the client that is having the error.

The whole console log has the potential for being relevant. I've seen mods that were not installed correctly that were easily identifiable by the log. Take Optifine for example. If I see it in the log under the NEIPlugins, in the mods folder not the instMods folder, then I know that it was installed incorrectly. You can also check to see if a mod is showing up in the log or if it may be a wrong version. Or not the most up to date in some cases if the file name lists the version number.

 

[JerryFrankson]

Thank you very much!
Thanks to you I've been able to add a few different mods and I plan on adding some more. Something strange happened when I added Biomes O Plenty, though. It shared an itemID with gregtech but it didn't crash. I only noticed when I right-clicked a berry bush and some kind of energy cell came out
It took me a little while to figure out how to include itemIDs in NEI's ID dump map and that NEI adds 256 to the number but in the end I managed to fix it!