Bought phone with avast preinstalled on it (ver. 4.0.7891).
Tried to update many times but without success: “An unknown error occured. Please, try again later.”
Automatic updates also doesnt work: “Attempt to update the virus definitions failed.”
Are virus definitions for version 4. discontinued?
Hi, update to V6.x, V4.x is way outdated.
Have newest avast on another phone.
I prefer old (ver.4) simple design, without ads.
V4 isn’t supported anymore.
So to make it clear - it’s impossible to download virus definitions from avast servers and have them up-to-date if using this version?
Well, I didn’t try but according to your report, it seems so. 
Thanks.
You’re welcome.
Even though we officially do not support the version 4.x any longer, the virus definitions updates should still work. (We tested it and they did.) Please try again. If it does not work, try the following:
- open Settings in your mobile device
- go to “Apps” (this may differ on some Android versions - just there, where all your apps are listed)
- tap “Avast Mobile Security”
- tap “CLEAR DATA” and “OK”
I keep getting a message on Avast Mobile Security telling me to resolve an issue, namely that my virus definitions are outdated. When I select “resolve,” it says it’s updating virus definitions but there is no evidence it has done so. The notice does not go away.
When I select “settings” and “updates” and check for an update it tells me I have the latest version, dated 2/3/19. Is this plausible?
I would like to either get rid of the message or be sure that I actually do have the latest virus definitions.
This was a known bug, fixed in version 6.16.
The definitions have actually been up-to-date all the time, only the date in the brackets is wrong.
Version 6.16 has been released to 100% of users by now, so you should be able to fix the problem by simply updating your Avast Mobile Security app.