Norton needs a scan after startup

I Use the PC almost daily. Not often but from time to time Norton Icon becomes orange. I need to do scan my PC and its fixed. I assumed this happens automatically? So why does this happen?

In the history log of Norton i noticed 5 lines (before i logged in) 5 times with the message: I allowed access for network resources for Download/Upload Host. This is from a system32 file from windows "BackGroundTranferHost.exe" and firewall rules are updated.

 

1 day, i use my Pc almost daily. I have had this before some months ago(twice). I am just wondering why.

How long since you last used this computer. If it has been more than a few days, Norton will flag this issue.