E: The package avast4server needs to be reinstalled

sudo gedit /var/lib/dpkg/status

in the document find this...

Package: avast4server

Status: deinstall reinstreq half-configured

Priority: extra

Section: alien.....

and change it to...

Package: avast4server

Status: install ok installed

Priority: extra

Section: alien....

Next go to the .deb installation package that you downloaded and open it in archive manager. Extract to your hard disk. You can now browse to these files to find the 'data.tar.gz' file which is another archive. Open this as 'root' and find the file 'avastd' -- it's in the directory (within the archive) called '/./etc/init.d/' As 'root', create in your filesystem a directory called /etc/sysconfig/ and then extract 'avastd' to that directory.

Start Synaptic. It will identify a broken link which is the 'avast4server' package. You can select this to do a 'Complete Removal'

Removal proceeds without error!