As the title says

[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: mods.railcraft.common.blocks.aesthetics.post.ItemPostMetal@104a5b3c
[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: mods.railcraft.common.blocks.aesthetics.post.ItemPostMetal@51d9da4f
[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: net.minecraft.item.ItemBlock@6671782f
[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: cofh.thermalfoundation.item.ItemLexicon@75a0859f
[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: cofh.thermalexpansion.item.tool.ItemWrench@6f2889a3
[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: cofh.thermalexpansion.item.tool.ItemIgniter@77a20bfe
[23:09:29] [Client thread/ERROR] [NotEnoughItems]: Failed to find identifier for: cofh.thermalexpansion.item.ItemFlorb@7193a4d9

IDK if this is NEI problem or this mods . If I am just stupid , and didn't need to report this Ignore .

Thanx -Crunk

I don't have the slightest clue what "Failed to find identifier" means, so I'm going to close this due to lack of further info.

@CovertJaguar I thing is something about the unique identifier for the RC's items

NEI Code
FML Code (GameRegistry)
FML Code (GameData)

I don't have enough knowledge to say what is going wrong here, but this could be useful.

This may be fixed in 9.5, but since the OP doesn't specify a version....