When you try to activate Windows Vista by using the Windows Vista activation process, you may receive an error code or an error message. This article contains a list of Microsoft Knowledge Base articles that can help you troubleshoot these error codes and error messages.

Just locate that error code or error message in the following list, and then follow the instructions.

Error code 0xC004C003

The activation server determined that the specific product key is in use.

This error code indicates that the product key that you entered has already been activated, and you must obtain a different product key.

Error code 0xC004E003

The Software Licensing Service reported that the license evaluation failed.

This error code indicates that you must rerun the Windows Vista activation process.

For more information about error code 0xC004E003, click the following link:

950755

Error code 0×80072EFD

A Connection with the server could not be established.

This error code indicates that there may be issues with your Internet connection. Verify that your Internet connection is working, and then try to activate Windows Vista again.

For more information about error codes 0xC004C003, 0xC004E003, and 0×80072EFD, click the following link:

931276

Error code 0xC004F050

The Software Licensing Service reported that the product key is invalid.

For more information about this error code, click the following link:

938450
950756

Error code 0xC004F061

The Software Licensing Service determined that this specified product key can only be used for upgrading, not for clean installations.

For more information about this error code, click the following link:

930373

Error code 0×8007000D

Unable to Open the License. The Data is Invalid.

This error code indicates that the initial download may have been corrupted, and you may have to download the package again.

For more information about this error code, click the following link:

930378

Error message

The Product Key You Have Entered Will Not Work With This Edition or Version of Windows Vista.

If you receive this error message, you may have inserted a product key for an edition of Windows Vista that does not match the installed edition.

For more information about this error message, click the following link:

949744

Error message

The Windows Vista (product version) product key you typed is invalid for activation.

If you receive this error message, there may be an issue with the installed version of Windows and with the product key that you used.

For more information about this error message, click the following link:

937768

Error message

To Use the Product Key You Entered, Start the Installation from Your Existing Version of Windows.

If you receive this error message, you must first start the computer by using the currently installed version of Windows. Then, start Windows Vista Setup.

For more information about this error message, click the following link:

947214

Error message

Your Activation Period Has Expired.

If you receive this error message, Windows Vista may not have been activated within the 30-day activation period, or there may have been significant hardware changes on the system.

For more information about this error message, click the following link:

925616

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