Packages not downloading to a few Package Servers

Hello,

I have an off issue where packages stop downloading to 3 out of 6 Package servers in our environment.  We get the error shown in the picture.  All of the folders have the same permissions set that are on the 3 other servers that work.  If I restart the Altiris Agents on the 3 non working servers,  the packages download fine,  but after a while we start getting this same error.  I have no idea what could be causing it.  I'm getting tired of stopping and starting the Altiris agents everyday on these 3 servers lol....

Thanks,