In your case should help if you got to Settings->Active Protection->Web Shield-> Customize->Uncheck “Enable HTTPS Scanning”
Martin
P.S. what you like to much about Win XP? 
We know a lot of users still use it but we don’t know why
Very simple. I have some really good software that runs on it (Pro audio stuff). It’s reliable and fast. If I were to update that system to a new OS I would lose so many years of data and programs that will just not work on them. If you really don’t know why we like XP I am thinking you never had the opportunity to use it for any length of time which is the case for many computer users that have not been at it since the first Commodore 64 and Apple … even before truth be told 
We watched the migration, saw how MS likes to screw up every 2nd OS. Great marketing for them, for us? Not so much. The old saying “If it ain’t broke, don’t fix it” comes to mind.
I am pretty sure I did at some point turn off HTTPS but so many important websites use it so if that will leave it vulnerable, I am not certain it’s a great solution.
Does this mean there will be no change to the existing product to address our issues?
Cheers
Is your XP up to date with all the updates ? Is it 32 or 64 bit OS ?
"If I were to update that system to a new OS I would lose so many years of data and programs that will just not work on them. "
Windows 8 is a lot more tolerant of old software than any of it’s predecessors. Since Windows 10 is build on the back of Windows 8,
this also holds true of the latest version of Windows which will be released on 7/29/2015.
I had some very old 16 bit games that never ran on windows 7 but worked on Windows 8.
Give it a try, you may just be surprised. You could always try one of those programs you aren’t sure about on a friends newer OS.
Hello,
I just wanted to add my voice to the growing chorus about this issue…because I’ve been affected, too.
- I just updated/upgraded my Avast Free Antivirus 2015 to v10.3.2223 (just like some others I saw in this thread)
- I run WinXP as well (just like some others I saw in this thread)
- I get peculiar “invalid certificate” errors at some unexpected sites (i.e., google.com, netaddress.com {my email provider} and avast.com{!} are those I tried, and where the error also showed up)
But…
- I called Avast for support (7/26/15, 11:30pm ET, usually GMT-5) and the technician (Benjamin) insisted that this was my computer’s fault, and not Avast’s for supplying a bad update.
- He claimed to not have heard of this issue before my call (do they NOT read these forums?)
- He then insisted that I’d need to pay for “Tier 2 Support” that he said I needed to fix this.
- He THEN said that I should talk to Microsoft for further assistance because (again) it was my computer (which he kept saying was running “Windows HP”, not XP, while besmirching MY computer knowledge as, he insisted, necessarily being less than his – I have my doubts) causing this as far as he was concerned…even though this thread intimates that it was, indeed, Avast’s update, instead, as I suspected.
So, anyway…
I’m posting here so that I can hopefully receive an update of an imminent(?) post from someone authoritative and knowledgeable at Avast with more information. I hope it comes soon…
Thanks,
Bram
Report your experience to Vojta Nekvapil: nekvapil[at]avast.com (3rd Party Support Manager)
Thank you for responding, Asyn.
Is this “Vojtech”, who posted in another thread here, wanting to see logs related to this issue?
Thanks again,
Bram
Nope.
PS: Workaround (XP): Disable HTTPS-Scanning in the web shield.
Thank you, Asyn. Also, it took me a while to figure out how to do so, but I’ve implemented the workaround. Here’s hoping (a) that it works, and (b) that it won’t reduce my protection to an unacceptable level.
Thanks again,
Bram
You’re welcome.
Hello
I’m here to say that the issue is not on XP only. I have win 8.1 and my PC is affected. Since the update pages on IE, Chrome, Opera, Firefox seem to load forever. Downloads are very slow in general. When I disable Avast everything is back to normal. When I enable it slows down or blocks programs. It affects Teamviewer which is sometimes connected, sometimes not connected to server. When not connected and I disable Avast it connects immediately. I’m using an executable jar file to remote view/control my android devices and it’s blocked by Avast now. I used an android emulation under oracle virtual box. I lost it after the Avast program update. I could not recover it because when I did system restore to previous point it said Avast prevented that. I have two other computers which have not version 10.3.2223 (they are set to manual update) and they work without problems. On the affected computer I’m sure Avast was configured to “ask when an update is available”, but it updated without asking after a PC restart and then the problems began.
I hope the issue will be addressed not only for XP but for all affected platforms.
Asyn,
That address doesn’t work as emails sent there get kicked back because the user is “Unknown”. Are you sure there’s no typo?
Bram
nekvapil(at)avast.com
The address is correct simply replace the (at) with the @ symbol.
I did that, bob3160, and this is part of what came back:
“nekvapil@avast.com: host mx2.avast.com[91.213.143.6] said: 550 5.1.1
nekvapil@avast.com: Recipient address rejected: User unknown in virtual
mailbox table (in reply to RCPT TO command)”
Bram
I change the [at] to the normal email @ ?
This is a valid email, I have just sent an email to that address and it appears to have gone through. I have referred him to your post.
EDIT: That email has just bounced back.
Update Avast Program vs.10.3.2223 on July 25, 2015…bad news!!
Running XP SP2, Have respected Avast for years…until alerts of the blocking of Mozilla, facebook, startpage, and even Avast sites themselves. Restore back to 2015.10.2.2218 seems to have worked for now. ignoring Pop up telling me to update Avast Program until it gets fixed.
You could have saved some trouble by just disabling the HTTPS scanning in the version as mentioned in Reply #20 and Reply #27
Yes, bob3160, thank you, I’m one who did that…disabling HTTPS as you showed…but the idea is that one shouldn’t HAVE TO do that in order to have Avast run as intended.
This is a bug in the update that Avast will hopefully be fixing soon. I surely hope so anyway…
Also, given that I and someone else have indeed found that the nekvapil@… address isn’t working, do you (or does anyone) have an alternative?
Thanks again,
Bram Weiser
I have already alerted one of my contacts at Avast of the email problem.
Remember it’s Sunday today. I don’t expect any answer till tomorrow.