Install problem in WDSC V6

I am attempting to install WDSc version 6 via the CDs onto an XP machine.
The installation terminates during disk 3.
I have used the same set of CDs on other XP machines without problem but 
cannot seem to get past this point on this machine.
Here is the error excerpts from the log file.

(Oct 11, 2005 10:04:35 AM), Install, 
com.ibm.rational.cdi.archive.CDIInstallArchive, err, ProductException: 
(error code = 601; message="err"; additional data = 
[b_rwdi:java.util.zip.ZipException: invalid entry CRC (expected 0xa1e7108c 
but got 0x3ae16565)])
STACK_TRACE: 12
ProductException: (error code = 601; message="err"; additional data = 
[b_rwdi:java.util.zip.ZipException: invalid entry CRC (expected 0xa1e7108c 
but got 0x3ae16565)])
        at 
com.ibm.rational.cdi.archive.CDIInstallArchive.install(CDIInstallArchive.java:390)
        at 
com.installshield.product.service.product.PureJavaProductServiceImpl.installProductAction(PureJavaProductServiceImpl.java:1916)
        at 
com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct.getResultForProductAction(PureJavaProductServiceImpl.java:5195)
        at 
com.installshield.product.service.product.InstallableObjectVisitor.visitComponent(InstallableObjectVisitor.java:369)
        at 
com.installshield.product.service.product.InstallableObjectVisitor.visitInstallableComponents(InstallableObjectVisitor.java:333)
        at 
com.installshield.product.service.product.InstallableObjectVisitor.visitProductBeans(InstallableObjectVisitor.java:133)
        at 
com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct.install(PureJavaProductServiceImpl.java:4563)
        at 
com.installshield.product.service.product.PureJavaProductServiceImpl$Installer.execute(PureJavaProductServiceImpl.java:3758)
        at 
com.installshield.wizard.service.AsynchronousOperation.run(AsynchronousOperation.java:41)
        at java.lang.Thread.run(Thread.java:566)

(Oct 11, 2005 10:07:15 AM), Install, 
com.installshield.wizardx.actions.ExecWizardAction, err, 
com.installshield.util.ProcessExecException: CreateProcess: "C:\Program 
Files\IBM\Rational\SDP\6.0\updater\eclipse\jre\bin\java.exe" -cp 
"C:\Program Files\IBM\Rational\SDP\6.0\updater\eclipse\iupdater.jar" 
com.ibm.orca.SilentSetup -radirwdi -del "C:\Program 
Files\IBM\Rational\SDP\6.0" error=3
STACK_TRACE: 6
com.installshield.util.ProcessExecException: CreateProcess: "C:\Program 
Files\IBM\Rational\SDP\6.0\updater\eclipse\jre\bin\java.exe" -cp 
"C:\Program Files\IBM\Rational\SDP\6.0\updater\eclipse\iupdater.jar" 
com.ibm.orca.SilentSetup -radirwdi -del "C:\Program 
Files\IBM\Rational\SDP\6.0" error=3
        at 
com.installshield.util.ProcessExec.executeProcess(ProcessExec.java:180)
        at 
com.installshield.wizardx.actions.ExecWizardAction.executeProcess(ExecWizardAction.java:412)
        at 
com.installshield.wizardx.actions.ExecWizardAction.run(ExecWizardAction.java:457)
        at java.lang.Thread.run(Thread.java:566)

Any help appreciated.
Robert