CraigB
3
Hi tjunk, avast does scan for malware+spyware+trojans but it is always good to add some extra protection and one of the best tools out there is malwarebytes and for the small fee of $25 you get the life time license for the pro version or just stick with the manual scanning of the free, another good addition is winpatrol which will monitor your host file and alert you to any changes in your system.
You have not mentioned what version of windows you are running which can be beneficial for further advice.
Also a good firewall can be useful to, especially if you running xp as it’s firewall defences are quite pathetic, vista is not much better and win 7 is alot better but still without outbound protection, good firewall’s are privatefirewall (very strong and probably the lightest firewall there is), online armor (also strong and very simple but a little heavyer), outpost firewall (very good and light also,has good review’s but i have not used this one, there are several member’s on the forum that do) comodo (used to be good but has become very bloated and heavy, plus it has always been a difficult firewall to setup).
That will get you started 