Hi Dave,
The first thing I'd suggest is look at what Java version you're using. In LW help > about will show you. If you're using Java 1.6.0_01, try reinstalling this older version (a few people have had trouble with the latest Java). Use the JRE offline installer & remove your original Java before installing this other one.
Java SE Downloads - Previous Release - JDK 5

If you're using Vista, you'll have to run Java 1.6. In that case, reinstall 1.6.0_01. Use the JRE offline installer & remove your original Java before reinstalling.
Java SE Downloads

If you get stuck & nothing's helping, get back to us with your system details
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