353 is internal number of this uupdate (its number is written in Avast's registry key). You can check if AvChrome.dll.sum file is present in your Avast program folder (it probably means uupdate was delivered on your machine). You can also run AvEmUpdate.exe manually to check for all available uupdates.
So... How do I know my avast! is running the latest version already (with the patch)? I've tried uninstalling and downloading the offline installation file from this forum and the version doesn't change and the same problem of avast! service not starting happens to me. I can't even start through services.msc or anything. I've reset my PC by which I mean I did a clean reinstall of Windows 10 about 3 times (erasing the disk and everything)... I think I don't sleep well since April 30 because Windows broke everything with the spring update. And I'm doing the resets just to get the antivirus working and it simply doesn't and avast! is the only free antivirus, in my humble opinion, that has the security level of a paid antivirus with all needed safety guards and more and I plan to pay for it if I use in a professional state, or if I need to use in my future workplaces. And you carry a lot of responsibility because a lot of people use your software and it's really good! Because without you, well... I tried Avira after [and before too, but that's another case] that avast! didn't work and it froze the PC (maybe because of the Windows 10 update too). At first, it worked like a charm, like avast! does, but then, it didn't start correctly and showed a "service couldn't start on time" red bubble error in eventvwr. And, before I saw that, I thought it was my hard disk dying; but it was just the antivirus trying to restart itself constantly or something like that by some bug I don't know (that started after the Windows update too): result: BSOD. The Avira scanner was awesome and it had a pretty clean new UI (maybe the new UI has the same problem?). What I mean is you are almost a monopoly in free security and without you I have no other solutions so please help me. I love you. <3 Since Windows XP using your products.