Apt-get error

[Sander Nagtegaal]

Failed to fetch 
http://ftp.yellowdoglinux.com/pub/yellowdog/apt/3.0/base/pkglist.update  Size 
mismatch
Failed to fetch 
http://ftp.yellowdoglinux.com/pub/yellowdog/apt/3.0/base/srclist.update  Size 
mismatch
Reading Package Lists... Done
Building Dependency Tree... Done
E: Some index files failed to download, they have been ignored, or old ones 
used instead.


This is the error I get when I want to run apt-get. Yum doesn't work here and 
I like apt-get better so I want apt-get to work. What to do with it?