Scan never goes beyond 0%

I have tried several times to do a scan, but it sits a 0% even after running for several hours. The version I am running is 17.5.2303 (build 17.5.3585.203). Any idea what is wrong? My O.S. is Windows 10. After all the years I have been running Avast Internet Security, this is the first time I can recall having any problem to speak of.With all the issues out there now a days, I definately want my AV to be working properly. :o

Have you tried avast repair?

Repair Avast:
Control Panel> Program and Features (Add/remove program)>Select Avast> Select Repair. Reboot when completed
https://www.avast.com/faq.php?article=AVKB204

If Repair doesn’t fix the problem, try the following:
Clean Install of Avast:
https://goo.gl/4Ptzkf
If you need additional help with the Clean Install, watch this:
https://youtu.be/p-h3myRD51A

I have exactly the same problem. I can run Smart Scan and boot time scan but not full virus scan.
Never had this problem before. In programs and features when selecting Avast there is no repair option. I am on windows 7 I would be interested to know if you fix it and how.
Dave

in programs and features select Avast and then “change” - the repair option should come up

Did you read the reply and answer already given ???

In programs and features when selecting Avast there is no repair option. I am on windows 7 I would be interested to know if you fix it and how.
Did you click the windows 7 button in guide? > https://www.avast.com/faq.php?article=AVKB204

I did the repair and reboot, but it made no difference. The “Smart Scan” works, but that is all.

I am tempted to do a complete uninstall and then a complete reinstall, however I am concerned what will happen to my license. I have a three license version, one for my main computer (this one with the problem), my laptop computer and one for my Weather computer. The 2nd and 3rd computers work fine and they all run Windows 10. If I completely uninstall the copy off my main computer, will this mess up my license? :-\

Your license should be fine, there isn’t a restriction on the number of installs but the number of systems it is installed on. Ensure that you still have a copy of your license file before you start.

You could unlink the existing troublesome installation from your my.avast.com account. Or delete that device (installation) from your my.avast.com account first, that should certainly allow you to reassign it to the clean install.

People, this was discussed with the developers and, right now, they need the support package to reproduce the error.

Please follow these steps:
First enable debug logging: GUI > Settings > General > Maitenance > Enable debug logging
Then try to reproduce the error.
And then create a support package and submit it (guide here: https://www.avast.com/en-us/faq.php?article=AVKB33) and post here the ID of the created package so we can find it.