[CentOS] YUM Parse Error

Hi All,

please, what is causing this error.? Cheers.

Mark Sargent.


Setting up Install Process
Setting up Repos
addons                    100% |=========================|  951 B    00:00
dag                       100% |=========================|    0 B    00:00
//var/cache/yum/dag/repomd.xml:1: parser error : Document is empty

^
//var/cache/yum/dag/repomd.xml:1: parser error : Start tag expected, '<' 
not found

^
Cannot open/read repomd.xml file for repository: dag
Error importing repomd.xml from dag: Error: could not parse file 
//var/cache/yum/dag/repomd.xml

UPDATE:
well, how interesting is that. That file referenced in the error above, 
is actually empty. Wasn't before. What r my options here.? Cheers, again.