Check if your computer has Avast security software installed, if it does then temporarily disable it.
If you still cant use your ID-card then:.
Insert ID-card in the reader and try again.
Remove card reader and reconnect it with USB port.
Close all browser windows – NB! Always use the Quit button as otherwise the browser can stay working in the background.
When authentication doesnt work after digital signing:
After digitally signing with ID-card in web browser it may not be possible to authenticate during the same browser session.
DigiDoc3 client and ID-card utility have to be closed for authentication and digital signing in web browsers to succeed, close them with QUIT menu choice or with CMD+q.
Make sure that ID-card browers add-on’s are enabled, instructions can be found at.