I upgrade my forge version from an older 2611 version to the current recommended build of 2705. Upon loading of the world I noticed many Industrial Craft blocks are purple and named as "Invalid" which is odd. So I also updated to the latest industrial craft build just in case I needed a newer version with this version of bukkit. Did not fix the problem however. I am using industrialcraft-2-2.8.83-ex112.
The mod seems to be loaded, and in some cases there are still working blocks. Here are some screenshots showing better what I mean:
In the image below I am trying to show that the geothermal generators I am on top of are there and not invalid, and you can see the copper cable from ic2 also there. Yet for some reason there are still invalid blocks seen in the pic, which oddly enough are also copper cables. I am a bit confused how some ic2 copper cables are present, yet some are invalid. Seems a bit odd to me. Not consistent. However the generators don't seem to be working anymore that are there. The batbox there does seem to function. New geothermal generators placed seem to work fine. Luckily I don't have a huge deal of ic2 stuff in the game so worst case I can rebuild it all in creative. Not ideal to do, and I'm worried it'll happen again in the future when I have more ic2 things in my world so I kinda want to figure out what happened here.
And then this image below is just showing that the mods items and everything are being picked up as loaded fine: