Had an issue with IE upgrades in the recent past where after the upgrade multiple pre-existing profiles would state they were in “Enhanced Security Mode” despite that mode being disabled. New profiles would work fine and Administrator usually did as well.
From what I’ve been able to track down, MS hasn’t figured out the exact circumstances that cause it. Fresh installs w/ upgrades before anyone logs in seem to work fine in my experience. Some profiles would also work fine despite being similar to ones that did.
Searches brought up multiple hacks to fix it. One is to make a login script that modifies the registry like so for every user:
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings] "IEHardenIENoWarn"=dword:00000000 [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap] "IEHarden"=dword:00000000
The best solution I found, though, was to use GPO and force a setting for the Internet Zone. Forcing it to Medium or whatever level appears to get pass the enhanced security issues and things work like normal.
Under either User or Computer depending on how you have GPO setup you would want to enable and set a level for:
Administrative Templates>Windows Components>Internet Explorer>Internet Control Panel>Security Page>Internet Zone
Not ideal but it is the best I’ve found