I’m seeing the same behaviour on a freshly installed Win10 1803 / Steam / AoE HD 5.8 setup - the launcher runs fine, but when I click Play (or if I bypass the launcher and run AoK HD.exe directly) I get a Critical Error dialog box saying “SteamAPI_RestartApplIfNecessary() has been triggered. Aborting startup.”
Verify Game Cache passes and I’ve tried the suggestions in this thread (bypassing the launcher and deleting player.nfp), but no joy. Happy to supply more info if someone can tell me where to look.
EDIT: I’ve just run dxdiag to make sure the AoE installer hadn’t messed up DirectX, and I noticed a bunch of crash entries at the bottom of the file you get by clicking Save All Information:
Windows Error Reporting:
+++ WER0 +++:
Fault bucket 2167449707191722813, type 1
Event Name: APPCRASH
Response: Not available
Cab Id: 0
P1: AoK HD.exe
I’m guessing this means it crashed while calling the graphics driver - I’m running on a Dell XPS 15 L521X with integrated Intel HD Graphics 4000 / GeForce GT 640M, and the P5 value in the error report is the Nvidia driver version.