I wanted to install express 11G on my laptop and during the process of unzipping I somehow managed to delete most of the directories in the 10G directory.
This results in !!G refusing to install as there is it still sees the XE service as existing. I also cannot de-install the 10G installation as the files are missing but it still shows as installed on the programs and features list.
How can I resolve this as I would dearly like to continue exploring the functionality of Apex 4.2 on the 11G DB without having to reload my machine completely.
I think you are posting to wrong forum. This is Application Express forum.
Oracle Database Express Edition (XE) forum is Oracle Database Express Edition (XE), where you might get help for install/uninstall problems of XE database.
Anyway check if documentation helps
BTW, APEX 4.2 should work on 10G XE.
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