Error "Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server" in EngageOne ContentAuthor

Product Feature: Administration Client

Issue

The following error occurred while creating a new conditions in EngageOne Content Author 6.0.1232.0.

Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server. The status code returned from the server was: 413

Cause

The amount of information being passed by the AJAX interface is too large for the default IIS setting.

Resolution

UPDATED: July 9, 2019
The IIS configuration "UploadReadAHeadSize" should be increased.
For more information see:
http://forums.asp.net/p/1109321/2983177.aspx