PC Tools Antivirus users

I've just installed PC Tools AV and it's blocking emails, both sending and receiving, tried it on 2 machines and it's same on both. The only way I can get it to work is by turning off email scanning, but it's put a doubt on the integrity of the prog.
Anyone else fould the same or have any ideas please.
Or any ideas for a light weight AV would be welcome.
Used to use Avast but it seemed to be bogging down my PC lately.

Cheers.

have a look over at Wilders Security - Panda's new AV available on 90 day trial.But not really suitable for slower older PC's imo.

Thanks steve,
I've decided to give Avira a try, seems ok so far.

djh22