In Safari 6 and higher, Java applets are disabled by default.
Please follow the steps below:
Step 1: Go to Safari > Preferences.

Step 2: Click on Security at the top, then click the Manage Website Settings…button.
Step 3: Click on Java in the left column, then next to mydlink.com. In Safari 6.1 and higher, select Run in Unsafe Mode. In Safari 6, select Allow Always.

Step 4: Click the Trust button in the window that appears.

Step 5: Click the Done button to apply your changes.