@ njbuch - As suggested by Architect a battery for RTC would be the easiest solution. If you realy can’t use a battery there might be a compile time option. I haven’t tried it but this would be my approach.
Create a small windows console program that creates a text file and write the current system time to the file.
In visual studio project setting.build events you edit pre-build where you call your console application.
Include the text file as a resource
In your managed app you read the resource content to set the clock