Cant Install Software

[Helena]

From some reason I cant reinstall my virus or firewall
software. I also have errors when installing other
software. I noticed this started happening after a
defrag - is it possible something has happened before of
this? I dont seem to be able to "restore" either - have
I lost an important system file, and do I need to do a
restore of my copmlete system?

 

[Frank Fallon]

It does sound as though you need to clean re-install.
Often faster than repairing.
http://home.kooee.com.au/kingul/stablexp.html