I downloaded Lightroom 4 upgrade and cannot open the installer
Without any error messages it is impossible to tell if both of these issues are related and what is causing the failure to install.
Mauryk1 you may want to try invoking the installer by right clicking and selecting Run as Administrator. This might at least give an error message which we can look at.
Ivo,
There is some trouble from the Microsoft side which we are aware of.
Please refer to the documentation for the same
http://helpx.adobe.com/lightroom/kb/lightroom-43-doesnt-install-window s.html
Mandhir
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