Now, I really don't mind ads in free software. I mean you openly state that in exchange of letting me use the product for free you get to show me ads - fair enough. Similarly if the free product has feature limitations.

Avast however is becoming a prime example of what a free product should not be like.

I was a happy Avast user since around 2005. Few years ago pop-ups started appearing "OMG! Your boot time is 15 secs. There are 836934 problems causing slow-downs. Buy Avast Pro to solve them". OK, this is slightly annoying. I don't mind ads but I hate those kind of scare-crap tactics. Still I decide to keep Avast...

Then, few months later Skype starts mysteriously opening up on start up. I check Skype's settings; make sure all autostarts are disabled. Check the registry.. nothing. It still happens. Then by chance the culprit is found: Avast's recent update has enabled an option to automatically scan and update all my installed software. I'm really pissed now, because I like updating my software myself, and I don't like Avast enabling this option without asking me first.

The final straw however was when I noticed that Avast started adding (again - without me enabling this option) a "scanned by Avast www.(avast's address).com" to all my outgoing emails. It took me time to find this option to disable it, but it seems Avast keeps enabling it from time to time when it updates. Now a program that tries to spread itself by attaching to a user's outgoing email without his knowledge is almost textbook definition of malware; something that Avast should be protecting me from.

And other bad practices of Avast include:
_ Silently deleting some files it thinks are malware, without any warning, despite having my settings set to "Ask me first". It's then makes it as difficult as possible to get to the Virus Chest to restore those files.
_ Auto-updating (program updates; not virus definitions), despite having options set to "ask me first". It often does ask me, but some updates are still made without my approval.
_ Attempting to install Google Chrome when auto-updating; you have to remember to opt out.
_ Installing, by default without asking me - not even an opt-out, features that I never wanted, like some idiotic browser addons.

So sadly, because I really loved it how it was initially, this means that after spending more than 10 years with it, Avast has to go.

I've decided to upgrade to a new antivirus, possibly a paid one. Avast Pro would have been an option if it wasn't for the crap they pulled.

So, I'm looking for recommendations. In particular I want:

_ Something lightweight: I don't want something that will affect performance worse than any malware could.
_ I just want virus protection: I don't need any crap that will "improve my PC's performance", "protect me when shopping online", "make sure my programs are up to date"... etc. I don't mind if that stuff is included, but it should be easy to disable. Specifically, nothing of this kind should be installed by default without my knowledge.
_ It should never remove anything silently. It should be easily to get to its quarantine area to restore items. It should be easy to create exclusions. I don't mind false positives; I know it can't be helped, but I don't want to spend ages looking for a way to restore a file that AV didn't like.
_ Simply, it should not treat users like idiots.

I'm thinking of getting Kaspersky. I've heard good things about it and it seems to be scoring well in "best AV rankings" lately (which I'm not sure how much to trust).

Does anyone have any experience with it? Any other suggestions?

Starting with Windows 7 the antivirus made by Microsoft has been surprisingly solid. For Win 7 you have to download and install it, but from 8 onwards it's built in. I've never had any issues or unpleasant surprises with it and it seems to do it's job well while being lightweight.

I heard good things about ESET, in that it has simple but solid feature set with the ability to more tightly control things. The only thing that makes me hesitate is that the premium version of Avast has a data shredder, which I would be interested in using when I transition to my next system.

$40 to $60 - ESET
https://www.eset.com/us/home/for-windows/

Iolo System Mechanic.

I remember having trouble turning the damn thing off on Windows 10 when I needed a to test few things. It was another one of those "I know better than you what you really want, so I'll just keep running". OK, I'll take a look but the price seems a bit steep, compared to other options. lol, it took me a while to realize that Iolo is Iolo and not you laughing.

Anyway, thanks but the fact that on its page the first point is "Boosts PC speed" and after that "Unleashes Internet speed" is probably an indication that this is not what I want...

I let the subscription expire on mine and never got around to setting aside money to renew it, but last time I used it, I'm sure it had an antivirus, as well as other maintenance tools like speed up, registry cleaning, defrag and stuff like that.

AV Comparatives might be helpful. You can use BleachBit for that.

Ah, that sucks. I haven't switched to 10 yet so I only have experience with it on 7 and 8. I'm on 8 at the moment and there's an option in the settings for easily turning it on/off, but they could have gotten rid of that (or obscured it).

hmmm. Kaspersky seems to have the best results there (combining both high effectiveness and low false positives). Bitdefender doesn't seem bad either.

I just hope Kaspersky Lab are better at virus removal than they are at maths. At the moment, for 3 devices, getting the 3 year version is actually more expensive (by 2 cents) than paying for each year separately. What a deal.

I recommend Kaspersky or Bitdefender for paid version, or Avira for free version.

I've been running AVIRA for years. Never had any problems with virus, runs on XP with Pentium D so it's rather leightweighted :-P

Avira was trying to push on me many of their extra features recently so I switched t Bitdefender and now I don't even know I have it and had no problem with viruses since then so as far as I can judge, it's doing its job well.

Is there a particular reason you think the full internet security version is necessary? As I said, all I'm really interested in is the AV.
Is there a particular reason you have against Kaspersky/Bitdefender free version?