Missing Update Files

I automatically do all the updates when they come in, but this time I got a message that said:

W: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/p/pam/libpam0g_1.1.1-2ubuntu5.2_i386.deb
  404 Not Found [IP: 91.189.92.166 80]
W: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/p/pam/libpam-modules_1.1.1-2ubuntu5.2_i386.deb
  404 Not Found [IP: 91.189.92.166 80]
W: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/p/pam/libpam-runtime_1.1.1-2ubuntu5.2_all.deb
  404 Not Found [IP: 91.189.92.166 80]

I went ahead and installed the rest of the updates anyway. It asked me if I wanted to install the others without these (like how am I supposed to know whether they will work without these other files? I had to guess. The computer still seems to be working though.)

But now it automatically reopens the software update panel when it comes up asking me to load these files that aren't there to load. If they are necessary, please fix the links. :-( If they aren't, then at least use the link to switch off the requests, so people's computers know they don't need them and aren't stuck in a request loop for files that aren't there.