I totally get that; the issue is unclear... seems like the computer is temporarily locking the files during a scan perhaps (which happens to show the red lock on the icons), or something entirely unrelated and possibly malware or another AV solution. I am running Windows 10 64-bit latest version, with Sophos Advanced Endpoint AV and MBAM Anti-Exploit running in tandem with it. Unrelated, but I've noticed CPU will be pegged by the sfc.exe service of the program, consuming upwards of 75% for a long time at random intervals, but usually first thing at boot... rendering the user experience almost frozen. I was thinking it might've been set to do automatic scanning at start-up or something, but I don't have any scheduled scans. I honestly have no clue what it could be; have you seen or heard of other reports of this red lock showing up on files as part of Immunet or ClamAV by chance?