For some time now I have been getting flase flags on my sites that have piwik code on them if someone is running Avast, Whether they be shopping carts of plain old WP sites, Avast flags as malware. I have reported it to avast support.avast.com but if other have the same issue it would be helpful for them to hear form more people. Currently I have piwik running on the WP-PIWIK plugin and it is getting flagged around the globe.
We have a similar problem with anti virus softwares… I have no idea why they do this 
It’s certainly hard to explain. I have contacted them also.
Good on you for reporting to Avast. that’s the way to go!
Thanks for the reply.
Maybe you can request everyone here to submit a false flag report to all the virus people. Or at leat the top 3 or 4. Imagine how many sites with piwik do not get visited because of this. The visitor wont turn off their protection to submit a contact form so no one ever knows. It could be a good 10-20% or more visitors leave seeing that false flag. I know on a commerce site I had after adding it our sales dropped 15% one month until a former customer emailed. I dont use it on commerce sites any longer.
Just got this reply.
[i]Thank you for contacting Avast Software s.r.o. with your concerns.
Our virus specialists have been working on the problem and it’s already fixed.
If you still can not access these sites, please update your Virus Definitions and try it once more:
open avast! and go to > Settings > Update > VIRUS DEFINITIONS > Update
If you need further assistance, don’t hesitate to contact me again.
Best regards,
Prokop Kalivoda[/i]
@rbv Very good news! Thanks for posting. do you think you will be able to ask one of your user to test if Avast allows Piwik after update?
have a good week-end!
Of course! As soon as I got the reply from Avast, I contacted two different users. Both turned avast back on and the websites cleared. I know there are other virus scanners out there that have issues, I dont have firthand experience, but everyone should check and write to the scanner people to get this cleared up. In my case, this time around, I was using a WP plugin for piwik, the prior time avast flagged (and I got no response from them) it was hard coded in the site. so I just know that now, for my sites at least, the wp-piwik plugin does not cause a flag but that does not mean that hard coded sites won’t someone needs to check that.