When I have avast! Home installed it slows down Internet connection.
Internet connection test shows about 2600 Kb/s with avast installed,
and about 3800 kb/s without avast installed.
Is this a bug in avast? Or is there something wrong at my end?
I’ve run the connection test 4-5 times, with and without avast installed.
And I get the same result, 2600-2700 kb/s with avast installed.
3800-3900 Kb/s without avast installed.
WebShield scans all HTTP traffic. A littel slowdown is necessary to do so.
If you think the Standard Shield protection is enough (which I think it’s not) well, disable the WebShield scanning.
But, maybe, the slowdown is being too big in your case… Hope that someone else could help…
Yup, it slowed my cable connection down also. Didnt like that. THEN, when I found out it missed a few trojans, I got rid of it. Since then, I’ve switched antiviruses,the one I switched to,BTW caught what Avast missed. It’s also a freebie 
Internet connection was alot more responsive also.
Good luck!
Before the Internet connection tests I scaned my computer with:
avast antivirus, Lavasoft Ad-Aware SE Professional and Webroot SpySweeper.
I also scaned my computer with another antivirus.
No virus, trojan, worms or other malware found on my computer.
Ad-aware found som tracking coockies, thats all.
No trouble if you post the name of the antivirus here.
Anyway, as you’ll see, this new antivirus does not seem to have WebShield or similar. You can’t compare avast! (with this feature) and the other antivirus that does not scan HTTP traffic.
You can, if you want less protection, just disable WebShield.
Sorry for the bump but hopefully this will help a future user. When Avast retrieved the new virus pattern this morning it dropped my connection speed significantly (google homepage took 10 seconds+). Didn’t make the connection immediately but noticed that just disabling WebShield as indicated in this thread did not fix the problem however disabling all of Avast seemed to fix it.
It was obvious that http traffic was being filtered as even pages with mostly graphics were taking forever just to load small graphics…think dial-up on a 28K connection. Tried a restart of my cable modem, router, etc (except PC) and behavior was the same. After a restart of my machine everything went back to the speeds that I’m familiar with (i.e. fast).
Thanks for the work on Avast.