I believe i've found a fix, at least for me.
Find the anti-cheat installer in "Steam\steamapps\common\FC 26\__Installer\EAAntiCheat". Open it as admin, on the drop down select FC26.
This showed me that i needed to update the anti-cheat but when i try to do that, it fails with a download manifest error.
Turning off IPV6 fixed that for me. Search for network connections in windows search. Right click whichever connection type you're using (Ethernet or Wifi) and select properties. Make sure "internet protocol version 6 (TCP/IPv6) is unchecked and then hit ok. Then run the update tool again, it should now update the anti-cheat no problem, it worked instantly for me. You can then turn IPv6 back on and launch the game.
https://www.reddit.com/r/electronicarts/comments/1ipt9ks/help_ea_anticheat_error/
Hope this works for you guys !! Such a stupid issue given that there's no feedback when the anti-cheat fails to run...
