Web App Builder does not launch in ArcGIS Enterprise Portal 10.8.1

[AjeyS]

Hi all,

I came across a strange behavior after deploying ArcGIS Enterprise Portal 10.8.1, I am unable to launch ArcGIS Web App builder. Web App builder page doesn't load correctly. please find the screenshot below.

Web App builder Failiure/Error

I get an error -TypeError: Cannot read property 'small' of undefined at t (main.js?wab_dv=2.16:37)

Did any one encounter a similar error like this? Any Idea how to fix it?

[wilcow]

I saw something similar in ArcGIS online.

Esri had me add a logo and update the shared theme settings in order to correct it - no idea if there's any correlation but you might try going to Organization --> Edit Settings and fiddle around with the shared theme. If you changed the Header background color, change it to white, and if you haven't added a logo under Shared Themes, add one

Again, no idea whether the issues might be similar in Portal and AGO, but this worked for me in AGO.

[Jelle_Stu_PR]

Yes I have. I came across this (very similar) issue when opening the new Configurable web apps. 

The issue turned out to be that my adblocker blocked it. Turning off the ad-blocker, or putting the domain on the white-list fixed the issue for me.

I must say, however, I had the issue in ArcGIS Online, not in an Enterprise deployment. 

[VMitch]

I also came across this problem in AGOL, not Enterprise and like Jelle-Stuurman above, turning the ad-blocker off worked for me. 

If it continues to be a problem, send support case to ESRI. 

[AjeyS]

Thank you, Will try this out.

[AjeyS · Accepted solution]

Hi Everyone,

Clean installation of Portal for ArcGIS resolved the issue.

[AbelE]

I had exactly the same issue with ArcGIS Portal 10.8.1. It was working initially then suddenly stopped working.

A clean install did not resolve it for me, this is possibly because I already had a lot of content in the site and had to restore the site data and configuration after the clean installation.

What did work was a simple setting change as suggested in this link

Quote from the link above: "We have seen a few issues such as this come into support recently; can you try uploading an image in ArcGIS Online under Settings > General > Shared Theme > upload image and see if this resolves the issue?"

It is apparently a known to ESRI Support.