Lookup failed for ID:

[paul massa]

I keep getting this when I reinstalled my skyrim

MASTERFILE: LOCALIZATION: Lookup failed for ID: 0x00012584 from strings file: Strings/Skyrim_English.dlSTRINGS!

would deleting the skyrim.esm maybe fix the issue and the strings as well being the kit says masterfile so I am guessing its in the skyrim.esm

 

[Bira96]

I just got an error message like this (literally, ten minutes ago, I freaked out and stopped playing to look for a solution) that replaced the name of my savefile with LOOKUP FAILED! It turns out you just need to go into Steam, right click on Skyrim, go into Properties/Local Files/Verify Integrity of Game Cache and that usually fixes it. You could also try a clean reinstall of Skyrim or your mods. This error message usually means a recent mod that you've added to your game hasn't loaded correctly and this error will pop up. But if you're paranoid like me, you can always remove your recent mods, and for Talos sake, BACK UP YOUR GAME, I CANNOT stress this enough! For 15 horrible minutes, I was panicking, deathly afraid that my game would corrupt itself the second I turned it off, right after I had completed the main quest, to boot! I am so lucky it didn't.
To back up your game, go into C:\Users\[UserName]\Documents\My Games\Skyrim\Saves, and copy your save files onto a SD card or Blank CD. You can use the backup system steam has if you want to, as well, but I find this much simpler.