If you have a Mac-
To troubleshoot extensions for a conflict, create a minimum extension set that includes only the extensions that Premiere requires. Then determine which extension causes the conflict. Add other extensions to the set, a few at a time, until the problem recurs.To create a minimum extension set:
1. From the Apple menu, choose Control Panels > Extensions Manager.
2. Save the existing extension set: Choose File > New Set, and name the set (for example, "My Settings").
3. Click Duplicate Set, name the set (for example, "Premiere Settings"), and click OK.
4. Choose View > As Folders.
5. Deselect all items in the Control Panels section.
6. Deselect all items in the Extensions section except for the following:
Apple Audio (Power Macintosh G4s only: Cubes and 733 mHz chips)
FireWire Enabler (DV only)
FireWire Support (DV only)
QuickTime FireWire DV Enabler (DV only)
QuickTime FireWire DV Support (DV only)
QuickTime -- QuickTime PowerPlug
Apple CD/DVD Driver.
These all need to remain selected to accommodate the device you're using.
7. Click your Restart button, and then restart Premiere.
Mac computers can usually find the right settings to configure, however one should never leave anything to chance, always double check your device and program settings.