EP6.0 installation error

Hello,

I am installing EP6.0 sp2 on a Windows 2003 Server. The installation was almost complete when it terminated with an error "The execution of metamatrix batch file terminated with errors. Return code 1".

However, I am being able to run the dispatcher & the Admin engine. But when I run the server, I repeatedly get and error as below

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SAP J2EE Engine Version 6.20 PatchLevel 63717.20 is starting...

Loading: LogManager ...

Loading: SystemThreadManager ...

Loading: ThreadManager ...

Loading: TimeoutManager ...

Loading: MemoryManager ...

Loading: PoolManager ...

Loading: PolicyManager ...

Loading: IpVerificationManager ...

Loading: ClusterManager ...

[ClusterManager]: ID000460: Can't open port 50020

Loading: ClusterManager returned false!

Kernel not loaded. System halted.

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Any suggestions to fix this ?

Thanks