why I have both installed... Avast 5 free If I paid for Avast internet Security

[REDACTED]

I paid for Avast Internet Security, but I have Avast free (Avast5, Alwil Software) installed too. Can I uninstall Avast free (I try once but don´t work)... so Can I delete the Alwil folders and clean the windows registry manually without have any problem? Thanks

[mchain]

You can use this cleaner from avast:  https://www.avast.com/uninstall-utility

Woooo!  Version 5 dates back from at least 2014, maybe earlier than that.

Follow instructions and place avastclear.exe on an administrator desktop.  Double-click and yes to enter safe mode.  Select ALWIL folders first reboot.  Uninstall AIS via programs and features -  reboot.  Run avastclear again, safe mode again, and select default folders for AIS - reboot.

Install AIS again and reboot.

Goes without saying to backup with an image in case of disaster first; best to leave registry alone unless you really know what you are doing in there.

In case you've run other a/v's in the past:  https://support.avast.com/en-ww/article/11/#artTitle