synaptic getting consistent errors on pkg intstalls - Help?

[Jeff.Hodges at KingsMountain.com]

In the past couple of days I've installed a boatload of packages using
synaptic with no problems. then it suddenly started giving errors on some
packages, and now it seems to be doing it for all. Here's the latest error
message..

E: /var/cache/apt/archives/i855-crt_0.4-0ubuntu1_i386.deb: Verification on
package /var/cache/apt/archives/i855-crt_0.4-0ubuntu1_i386.deb failed!

All the errors I'm getting seem to be the verification one like above.

Any ideas?

thanks,

=JeffH