ArcMap 10.8 Will Not Open After Install

[GabrielAttoun]

I installed and authorized ArcGIS Desktop 10.8. I can open ArcCatalog. I cannot open ArcMap. The splash screen makes it through Initializing License, hangs briefly on Initializing Application, and then disappears. No error message.

What I've tried:

• Disabling antivirus as well as excluding ArcGIS folder.
• Changing the Python path, as well as uninstalling and reinstalling Python (I had multiple versions installed)
• Uninstalling ArcGIS Pro
• Checking Event Viewer logs (nothing)
• Confirming that ArcGIS Administrator lists ArcGIS Desktop Advanced as authorized.
• Repairing installation of ArcMap.

[DanPatterson]

related perhaps, but this is for 10.7.1

It gives a few registry entries etc to check before reinstalling

Problem: ArcMap crashes during Loading Document launch stage (esri.com)

[curtvprice]

Also Resetting your ArcGIS application profile 

and: make sure your windows default printer is set to a real device (or PDF) with current drivers. 

[RobertBorchert]

Did you install Oracle 64 Bit?