Hi,
If you find a problem while installing Microsoft SQL Server 2008 R2 Express Edition (MSSQL) as follow:
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| Error Notification |
Usually it is because the MSSQL been previously installed and you plan to do a re-installation. To solve this, here are steps should be performed:
1. Find first product code and reverse it. In may case is 4AB6A079 and reverse it and become 970A6BA4. Copy it.
2. Run regedit.exe.
3. Go to "Computer\HKEY_CLASSES_ROOT\Installer\UpgradeCodes".
4. Right click on "UpgradeCodes" and choose "Find..." menu.
5. Paste the code and click "Find Next" button.
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| Paste the code. |
6. You will find the code then delete all folder containing the code (parent subkey).
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| After find key containing the code. Delete all parent folder. |
7. Make sure you don't find the code again by push "F3".
8. Try to run MSSQL again. If you find another product code. Do previous steps.
In my case, I did 6 times to delete the folder containing code.
That's all.