Remove IBM HTTP Server Manually
There are two ways how to uninstall IBM HTTP Server.
Automatically by running this command: /opt/IBM/HTTPServer/uninstall/uninstall
Or Manually only removing the /opt/IBM/HTTPServer directory is not enough. You have to also remove the file /opt/.ibm/.nif/.nifregistry (please, backup the file first, as it will remove other installed IBM websphere family product.
/opt/.ibm/.nif/.nifregistry