I’m a beginner in Java. I’ve tried two different applets now (one of which I borrowed from another site), both of which involved text fading and color changing. I put all of the HTML tags in correctly, and I have the right files uploaded, but the Java just doesn’t work. Instead I get a grey box with a message below that says “Applet can’t start: error: java.lang.ClassFormatError.”

I’m wondering if this might be a problem with file extensions, because I’ve had problems in the past with the renaming of uploaded three-letter file extensions from my Windows system to longer extensions such as .html, .java, and .class. Every time I upload a .class file, I have to change it from .cla to .class, and maybe somewhere in that process the file format has been screwed up. I’m guessing this because of problems I’ve had before with .html. Any help or suggestions would be appreciated.

The file name conversions between Windows and DOS drive me crazy, too. But judging from your error message, I’d guess the problem has to do withthe way you downloaded your class files. I always download class filesas raw data.

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