Is it ok to delete folder $AV_NLL, and its contents

Norton 360 for Windows
2

are you sure you do not need any quarantined files?

~ by my experience…$AV_NLL folder is created with an initial quarantine event…and $AV_NLL folder remains…until you clean install Norton.

you’ll need to temporarily disabled Norton - Product Tamper Protection to delete $AV_NLL folder.

~ related: https://community.norton.com/t/av-nll-folder-recently-found-in-my-system-but-used-by-norton/262622/14