I did what both of you said and I still get a fatal error on startup. I changed the compatability of the frostwire.exe file to windows 2000 Picture Here and the log4j.properties file does exist. The only difference I can see in the error messages is that it now says I have windows 2000 v. 5.0 installed instead of windows xp.

FrostWire version 4.10.0
Java version 1.5.0_06 from Sun Microsystems Inc.
Windows 2000 v. 5.0 on x86
Free/total memory: 2900160/4128768

FATAL ERROR!

org.apache.commons.logging.LogConfigurationExcepti on: org.apache.commons.logging.LogConfigurationExcepti on: No suitable Log constructor [Ljava.lang.Class;@1608e05 for org.apache.commons.logging.impl.Log4JLogger (Caused by java.lang.NoClassDefFoundError: org/apache/log4j/Category) (Caused by org.apache.commons.logging.LogConfigurationExcepti on: No suitable Log constructor [Ljava.lang.Class;@1608e05 for org.apache.commons.logging.impl.Log4JLogger (Caused by java.lang.NoClassDefFoundError: org/apache/log4j/Category))
at org.apache.commons.logging.impl.LogFactoryImpl.new Instance(LogFactoryImpl.java:543)
at org.apache.commons.logging.impl.LogFactoryImpl.get Instance(LogFactoryImpl.java:235)
at org.apache.commons.logging.impl.LogFactoryImpl.get Instance(LogFactoryImpl.java:209)
at org.apache.commons.logging.LogFactory.getLog(LogFa ctory.java:351)
at com.limegroup.gnutella.gui.Initializer.initialize( Initializer.java:89)
at com.limegroup.gnutella.gui.GUILoader.load(GUILoade r.java:41)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknow n Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Un known Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.limegroup.gnutella.gui.Main.main(Main.java:43)
Caused by: org.apache.commons.logging.LogConfigurationExcepti on: No suitable Log constructor [Ljava.lang.Class;@1608e05 for org.apache.commons.logging.impl.Log4JLogger (Caused by java.lang.NoClassDefFoundError: org/apache/log4j/Category)
at org.apache.commons.logging.impl.LogFactoryImpl.get LogConstructor(LogFactoryImpl.java:413)
at org.apache.commons.logging.impl.LogFactoryImpl.new Instance(LogFactoryImpl.java:529)
... 10 more
Caused by: java.lang.NoClassDefFoundError: org/apache/log4j/Category
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Unk nown Source)
at java.lang.Class.getConstructor0(Unknown Source)
at java.lang.Class.getConstructor(Unknown Source)
at org.apache.commons.logging.impl.LogFactoryImpl.get LogConstructor(LogFactoryImpl.java:410)
... 11 more


-- listing session information --
Current thread: main
Active Threads: 6

-- listing threads --
main: 1
AWT-EventQueue-0: 1
AWT-Windows: 1
AWT-Shutdown: 1
Java2D Disposer: 1
Image Fetcher 0: 1


-- listing properties --
LAST_EXPIRE_TIME=1136709284937


Any other suggestions? Thanks