After I uninstalled a fake version of Ofice 2007 I cannot open a official version of 2003 which was on the computer before

Uninstall whatever 2003 may have installed

Here is app to remove 2007
Clean uninstall of Microsoft Office 2007
Microsoft Office 2007 Complete Registry Removal and Deletion Uninstaller My Digital Life (http://www.mydigitallife.info/2009/01/03/microsoft-office-2007-complete-registry-removal-and-deletion-uninstaller/)

Reboot and you should be able to install 2003

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