I mean, I'm not waking up every day and deliberately deciding to look for things on my computer that could cause me to worry. It's not on my agenda of things to do. Like I said, I went to my C drive folder like I've done a billion times and noticed the folder. With the EEK thing I was concerned I had some malware after an Avast block alert from a website (unrelated to the Avast Program Files folder) and used a scanner I had used dozens of time with no issues. It picked up those results, I googled and it lead me to the thread created earlier this week by someone else with a similar issue, and I posted in there.
There was no executable file in the avast! sandbox folder, it was a small (16 kb) .DAT file, and I was already able to delete that file, so all I was left with was an empty sandbox folder. And i'll repeat: I don't have the sandbox portion of Avast installed or enabled as part of my Avast installation. So I googled how to delete it, found no issues or warnings from other people, and it lead to results from this forum and on this forum it was suggested to disable Self Defence mode, and the delete it from there.
No, I obviously did not delete the other C drive folders in the screenshot.