Missing Patch Error

All of a sudden I keep getting this error box saying that I have a missing patch for all of my textures. It also says I have missing patch for a BLUEWALL texture, and I've never even used that in my level! What are these patch things anyway? I can't find anything about them in the SRB2 Wiki, and they make my level crash everytime I test it! How do I get rid of this? :(

You need a new, clean lump of TEXTURE1 and PNAMES. The one you have might be broken somewhere.