Yum error message -- New twist

[Benjamin Sher <delphi123 zebra net>]

Dear friends:

I would appreciate your help with this yum issue. I can't use yum, and I 
don't have any idea what the problem is. Yesterday, I posted a message 
with the error message generated by the "yum list available |more" 
command. Now I am getting a new error message. Below is the new error 
message and at the bottom is yesterday's error message.

[sher localhost ~]$ yum list available |more
Error: Caching enabled but no local cache of 
//var/cache/yum/sl-errata/primary.xml.gz from sl-errata
Setting up Repos
Reading repository metadata in from local files
[sher localhost ~]$

[sher localhost ~]$ yum list available |more
Cannot open/read repomd.xml file for repository: dag
Cannot find repomd.xml file for dag
Setting up Repos
[sher localhost ~]$

Thank you.

Benjamin