This should pass once everything has been scanned once however if it continues you should perhaps consult Technical Support - it's free of charge by phone or online chat and linked under Useful Links at the top of this page.
Many years ago (VirusScan 7) the home product did have the ability to exempt individual files and folders from scans but now that only applies if an object is identified as a PUP (Possibly Unwanted Program) as too many people, gamers especially, were exempting everything and thereby wrecking their machines with malware as a result. The facility still exists in the Enterprise version but that involves bulk licensing of course.
You might consider storing all your important photographs on an external drive. Normally once they've been scanned once that should be it.
Thanks for that advice, Peter. I will have to talk to Tech Support, as this "mini" scan & delay takes place every single time a photo folder is opened. Every time. The delay varies, but it is a hindrance to workflow to be waiting 8, 9, 10, 11 seconds for a folder to open. One strategy I tried was changing folder options, so that open folders remain open until manually closed- this cluttered my taskbar and I then had to hunt for the right folder to re-maximize.
I tried adjusting some setiings in Real-Time Scanning, unchecking various boxes, but nothing had an effect on the folder-opening-delay, until I turned Real-Time Scanning OFF completely. Then all folders opened instantly. Perhaps the folders and their contents are just too "big," but that's an absurd limitation.
BTW, I do run a weekly back-up to an external drive of the entire photo collection. But it is not practical to edit them from there. This problem only began when I recently renewed my McAfee annual subscription, and downloaded the latest version of A-V Plus. This problem was not occuring in the previous version.
I agree it's frustrating and you should never have to turn off your real-time protection to do anything. There may be a bug which can be fixed so Tech Support would be a good idea in this instance. Make sure you point out to them that it just started with the new version.