ISC install error

[unixandtsm]

Hi all,
got the following error while installing ISC 5.5 on RHEL5_X86 box.
TSM server version is 5.5 and is on AIX server.

Following is the error from /opt/IBM/ISC601/log.txt

(Jul 21, 2011 11:25:41 AM), Install, ACProductAction, err, An error occurred and product installation failed.  Look at the log file /opt/IBM/ISC601/log.txt for details.
(Jul 21, 2011 11:25:41 AM), Install, ACProductAction, err, ProductException: (error code = 126; message="Check for previous installation of Integrated Solutions Console 6.0 fail
ed.  See /opt/IBM/ISC601/Tivoli/dsm/logs/ac_install.log for details.")
STACK_TRACE: 13
ProductException: (error code = 126; message="Check for previous installation of Integrated Solutions Console 6.0 failed.  See /opt/IBM/ISC601/Tivoli/dsm/logs/ac_install.log for
 details.")
        at ACProductAction.install(ACProductAction.java:590)
        at com.installshield.product.service.product.PureJavaProductServiceImpl.installProductAction(PureJavaProductServiceImpl.java:1923)
        at com.ibm.wizard.platform.linux.LinuxProductServiceImpl.installProductAction(LinuxProductServiceImpl.java:552)
        at com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct.getResultForProductAction(PureJavaProductServiceImpl.java:5202)
        at com.installshield.product.service.product.InstallableObjectVisitor.visitComponent(InstallableObjectVisitor.java:369)
        at com.installshield.product.service.product.InstallableObjectVisitor.visitInstallableComponents(InstallableObjectVisitor.java:333)
        at com.installshield.product.service.product.InstallableObjectVisitor.visitProductBeans(InstallableObjectVisitor.java:133)
        at com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct.install(PureJavaProductServiceImpl.java:4570)
        at com.installshield.product.service.product.PureJavaProductServiceImpl$Installer.execute(PureJavaProductServiceImpl.java:3765)
        at com.installshield.wizard.service.AsynchronousOperation.run(AsynchronousOperation.java:41)
        at java.lang.Thread.run(Unknown Source)
(Jul 21, 2011 11:38:05 AM), Install, com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct, err, An error occurred and product uninstallation faile
d.  Look at the log file /opt/IBM/ISC601/log.txt for details.
(Jul 21, 2011 11:38:05 AM), Install, ACProductAction, err, ProductException: (error code = 1; message="Uninstall failed.")
STACK_TRACE: 12
ProductException: (error code = 1; message="Uninstall failed.")
        at ACProductAction.uninstall(ACProductAction.java:635)
        at com.installshield.product.service.product.PureJavaProductServiceImpl.uninstallProductAction(PureJavaProductServiceImpl.java:1954)
        at com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct.processActionsFailed(PureJavaProductServiceImpl.java:5145)
        at com.installshield.product.service.product.InstallableObjectVisitor.visitComponent(InstallableObjectVisitor.java:374)
        at com.installshield.product.service.product.InstallableObjectVisitor.visitInstallableComponents(InstallableObjectVisitor.java:333)
        at com.installshield.product.service.product.InstallableObjectVisitor.visitProductBeans(InstallableObjectVisitor.java:133)
        at com.installshield.product.service.product.PureJavaProductServiceImpl$InstallProduct.install(PureJavaProductServiceImpl.java:4570)
        at com.installshield.product.service.product.PureJavaProductServiceImpl$Installer.execute(PureJavaProductServiceImpl.java:3765)
        at com.installshield.wizard.service.AsynchronousOperation.run(AsynchronousOperation.java:41)
        at java.lang.Thread.run(Unknown Source)

and

/opt/IBM/ISC601/Tivoli/dsm/logs/ac_install.log is below

********************************************************************************
Starting a new install instance at [July 21, 2011 11:25:31 AM EDT]
********************************************************************************


How to resolve this issue.
Thanks in advance!