ISSUE

If I try to register a Workflowagent in Administration then the applications crashes.

If I try it using regasccm.exe then the following error is shown: Fatal Error (3000): Fatal Error

CAUSE

One file of the WFA is probably still blocked by Windows.

SOLUTION

Try to unblock the DLL file (and sub used DLL files) using Windows Explorer. Select the file > Propierties > unblock

Powershell method:

Get-ChildItem "C:\path\to\folder" -Recurse -File | Remove-Item -Stream Zone.Identifier -ErrorAction SilentlyContinue

REFERENCES