Vishal,
I would still install the Logos version 4.4. Make sure all the lk*.exe and lk*.dll in the system directory will have the version 4.4 afterwards.
If you start with LabVIEW 6i and LabVIEW DSC 6 I would highly recommend an upgrade at least to LabVIEW 6.0.2 and DSC 6.0.2. This upgrade is free. If you start a project I would do it with LabVIEW 6.1 and DSC 6.1.
Anyhow, I hope the reinstallation of Logos 4.4 solves your issue.
Roland