Documentum CTS reinstallation failing Null Pointer

I went into an issue by a customer were I had to upgrade in place the CTS. When you have to upgrade a CTS on the same server you first have to uninstall the old version in order to install the new one. Unfortunately, the uninstallation didn’t end well and some folders or configuration haven’t been removed properly.

Removing CTS manually

If the uninstallation failed with the uninstaller, you will not be able to run it again to remove all the stuff, as it thinks that it has already be uninstalled. So you’ll have to remove the components manually.

1. Remove the 3 services for CTS: You will find 3 services with the name beginning with “Documentum”, remove them.
2. Remove the installation folder: By default the installation folder is located in C:Documentum, you can remove it or at least change its name.
3. There are some keys in the registry, normally you can keep it as it doesn’t prevent the software to be reinstalled. But note that you can search for “Documentum” in the registry to find all concerned keys.
4. Remove the DFC if it is still there (Add or Remove Programs).
5. In the targeted repository, remove the folders System/Media Server, System/Applications/Transformation and System/Applications/Rich_Media_services. It is where the transformation profiles are located. Note that you may keep it as the latest installers can dump them in order to replicate your configurations.

Running the installer fails with a null pointer

I had the issue where I did all the recommendations above, and when I ran the installer it failed with a null pointer. Even in the GUI I saw a path trying to install here: null/Documentum.

It is even impossible to change it manually as it’s a path generated by the installer itself. I thought it was due to the registry keys but it wasn’t, I changed a lot of them manually and nothing changed.

The issue came from a file that wasn’t deleted by the uninstallation, this file handles information about the previous installation, it is located here: C:Program FilesZero G Registry.com.zerog.registry.xml

You’ll have to display hidden files and folders. Delete this file and the installation will go smoothly now.