NemID is divided into "login" and "certificate". Therefore, your NemID may work when you log in, but fail when you try to sign, your certificate might be expired and therefore it must be renewed.
- You may have multiple signatures on your computer
- Your certificate may have expired
When choosing the employee signature, try choosing another one from the dropdown. Maybe the one you are trying to access is not active.
- Log in to medarbejdersignatur, click here
- Click on "My Employee Signature"
- Renew your employee signature