Microsoft released major update of Windows 10 in March, 2017. This is the update for ver 1607 released in July, 2016. You can identify when those major update is released by ver xxxx. First 2 digits is the year and last 2 digits is the month.
By this time around, Microsoft starts pushing this update as automatic update for Windows 10 users.
It appears Microsoft is trying more to push away some 3rd party anti virus programs promoting more for their anti virus program “Windows Defender”.
Although, Microsoft is saying their Windows Defender program can co-exist with 3rd party anti virus program, you will see some occasions that is not the case.
Take Symantec Endpoint Protection (SEP) ver 14 as an example (SEP is usually for corporate users), you have to uninstall any version prior to;
Symantec Endpoint Protection 14 MP1 14.0.2332.0100 February 17, 2017
Symantec Endpoint Protection 14 MP1 Refresh Build 14.0.2349.0100 March 16, 2017
(Both versions are considered current)
for successful update to the Windows 10 ver 1703.
And once your Windows 10 is updated to ver 1703, you are no longer able to reinstall SEP prior to the above version.
Most likely, this is another headache for SEP corporate users.
One more thing;
If you do not like Windows Defender tray icon appears on your task bar co-inside of your favorite anti virus tray icon, you can disable the Windows Defender icon using free software “Autorun Organizer” by Chem Table Software. Windows Defender tray icon pops up even you disable the program itself.
You should only temporary disable the Windows Defender Tray Icon not removing it as it might cause some issues later on.