This is for Grub users. To reinstall Grub to your MBR:
# grub grub> root (hd0,0) grub> setup (hd0) grub> quit
Some time ago clam decided they would stop using 'clamav' as the user and switch it to 'clam'. This is pretty annoying since all the config file and such use 'clamav'. Here's how to fix the file ownership after clam is updated:
It took me a while to find all of these but the find command helped a lot.