How to erase zero size files "unp*.tmp.mdmp"?

Avast Free Antivirus / Premium Security
1

There are many zero size files in the log directory.
They all having names like “unp*.tmp.mdmp”.
Seems the main “Awil Software” directory and its subdirectories cannot be changed from Read-only permission.
How can I clean-up and erase the many old zero size temporary files?
They are dated back to February 2006.
Thanks.

2

Temporarily disable the avast self defense module:

  1. Right click the ‘a’ blue icon on system tray.
  2. Programs settings > Troubleshooting (tab)
  3. Disable self defense module
  4. Delete that files.
  5. Enable self defense module again.