Accessing local files from a Web browser is for security reasons only possible with a certified applet. As an official certificate is very costly, jExifRead uses an unofficial certificate (fake certificate). As a result, your web browser will report, "the certificate comes from a company that is not trusted" and the "certificate has not expired and is still valid".

In order to get the applet working you must confirm the security dialogue with "Yes".
Powertek.de assures you that the applet only reads the image file you've selected and only analyse the metadata of the file.
No other data on your computer will be read and nothing will be send over the internet!