i installed arcgis enterprise on new machine
all component working well
just i have problem in web app building when start build new app
same error coming from portal and also from web app builder developer edition
kindly check the image for detail
At first glance there were two issues where customers removed their logo or didn't define one for the Portal and seemed to report similar behavior, would you try configuring a picture file for your Logo and see if that resolves the behavior?
Configure general settings—Portal for ArcGIS | Documentation for ArcGIS Enterprise
Did you set the general logo picture or the one for the shared theme? I would try both, but it may be more advantageous to open a Support case so an analyst can look at the behavior in more detail with you.