Hello,
I agree to Ramji Iyyer... It appears to be an issue with Windows Installer. The Windows Installer might be registered with a program that didn't install correctly, was cancelled, failed, etc
Try the following steps:
1. Uninstall the SEP Client
2. Re-register the Windows installer-
i) Go to Start->Run-> Type msiexec /unreg then press the "Enter" key.
ii) Go to Start->Run-> Type msiexec /regserver then press the "Enter" key
3) Install the SEP Client.
Please update with the status.
Thanks...