Can't uninstall xshell 4 [1]

I can't install an older build of XShell. The installer fails with "A later version of 'Xshell 4' is already installed on this machine. The setup cannot continue.", I have removed the installation folder. I use system is "windows 8".
Please help, this makes me unable to use XShell at all.

Program Ver. : Xshell 4

Please follow the instruction in the following page and try installing the software again:

Xmanager Knowledgebase : How to uninstalling software manually Failed to uninstall software

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