Has the machine been configured for DCOM and set to allow other HP products run QTP? Sometimes this setting get reset on a machine. Please try the below procedures.

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**To configure QTP you need to do the follow two things**.

Set up DCOM.

1. From start menu go to Start > QuickTest Professional > Tools > Additional Installation Requirements.
2. Select the 'Configure for Internet Explorer settings' and 'Configure DCOM settings' and other items if needed.
3. Press the 'Run' button and follow the wizard menu.

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**Allow Other HP tools to access QTP.**

1. From QTP Main Menu Tools > Options > Run
2. Place check in the box labeled 'Allow other HP products to run tests and components'.
3. Press 'Ok' button
4. Close QTP.