Hi Padma,
Fyi, With regard to your problem Ankur had already posted a useful article on
"Does QTP support MS Vista?" (
http://mercuryquicktestprofessional.blog...pport.html )
Please find the below for more info.
Working with Windows Vista:
* The security settings in Microsoft Windows Vista may prevent you from performing a QuickTest Professional-related installation, such as a patch installation, or connecting to a Quality Center project (either directly or from QuickTest Professional). This can occur when the User Account Control (UAC) option in Windows Vista is set to ON, and you have not yet connected to a Quality Center project (if relevant).
Workaround: To work with Quality Center, temporarily turn off the User Account Control (UAC) option, as follows:
1. Log in to Windows Vista as an administrator.
2. From the Control Panel, choose User Accounts > Change Security Settings.
3. Clear the Use User Account Control (UAC) to help protect your computer check box and click OK.
4. Connect to Quality Center as usual. After connecting to Quality Center, you can turn the User Account Control (UAC) option on again. Hereafter, you should be able to connect to Quality Center, as needed.
* Due to a problem opening DCOM permissions on Windows Vista, QuickTest does not run properly on a remote Windows Vista host from Quality Center.
Workaround: Run RmtAgentFix.exe from the \bin folder.
* On Windows Vista, QuickTest Professional seat licenses may not work correctly if you are not logged on as an administrator. (Note that concurrent licenses work as usual.)
Workaround: On Windows Vista, install QuickTest Professional and any QuickTest add-ins as an administrator. To do this, right-click setup.exe from the root folder of the QuickTest Professional installation CD and choose Run as administrator.
Hope it would solve your issue.