Without knowing the make and model of the computer and operating system, this is general.
How To Restore or Reinstall Microsoft® Windows® on a Dell™ Computer
Make sure to install the drivers in the correct order.
How to Download and Install Drivers in the Correct Order
A Dell OEM disk should install with no problems. If you made the Windows 7 - IMPORTANT Windows 7 Backup Disks to create then you can Restoring Your Dell Computer to Original Factory Installation with Dell DataSafe Local Backup 2.0
What is a Dell Service Tag and how do I locate it?
Original poster, If you have solved your problem, can you please mark the correct thread(s) with your solution. Thanks
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I have windows vista and have followed the instructions. While expanding files about 30 min into installilation I get an error. I have a Studio 1555 model number PP39L
If you can, try running the full diagnostics and report back any error messages.How to Run the Dell™ Diagnostics Utility