This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Applets run inside a "sandbox" which prevents them from accessing the client machine or contacting any server other than the one they were downloaded from. This is a security measure to prevent malicious applets from messing up your computer. You can get around this limitation by digitally signing your applet. Consult the Advanced Programming for Java 2 book for a tutorial.