Problems after installation on Ubuntu 10.10

I have just installed Avast on Ubuntu 10.10, following this procedure:
Command 1: wget http://files.avast.com/files/linux/avast4workstation_1.0.6-2_i386.deb
Command 2: sudo dpkg -i avast4workstation_1.0.6-2_i386.deb
Command 3: cd /usr/lib/avast4workstation/share/avast/desktop
Command 4: sudo ./install-desktop-entries.sh install
Then I started Avast from the Applications menu, inserted the registration key that I had previously got and the GUI appeared. I started the udpdate process and went on working on other matters
When I got back, all Avast icons and windows had disappeared and upon restart I got a message like “Deleted stale lock file '/home/…” and was asked again for my registration key. The same happened a couple of more times, then, after inserting my registration key once more, I got the following message:
An error occured in avast! engine: Unknown error no.42000
Can anybody help?
Thank you so much

Hi,

See if this helps: http://forum.avast.com/index.php?topic=57775.0

If you are a linux newbie then read this: http://forum.avast.com/index.php?topic=57775.msg487963#msg487963