Error at system startup: "Could not load type 'System.IdentityModel.Tokens.Jwt ..."

Some users reported the following error message with version 10.0.35 (and newer) when opening the browser:

There is a problem with the server

Sorry, the server has encountered an error. It is either not available or it can’t respond at this time. Please contact your system administrator.

500 Error

The following warning is present in the Event log:

Could not load type System.IdentityModel.Tokens.Jwt

This issue occurs only if the Build metadata cache when AOS starts setting is enabled in the System parameters:

The quick-fix is to disable the above setting. However, if we cannot start the system anymore, we can only do this via SQL:


After changing this parameter, we need to restart IIS (or IIS Express), and we will be able to start the system.

Please note that this bug is already fixed in Docentric version 3.4.7 which we are just about to release. After upgrading Docentric, we can enable the above setting without any issues.