When updating to the latest version of Noah 4 from either NOAH 3 or Noah 4, you get the message that ‘You are trying to install Noah System. However, another business system is already installed on your computer.


This message is telling you that there is a Noah business system (Noah Engine) or most likely a remnant of a Noah business system on the computer. 

  • If it is a full business system using Noah Engine, the location should get instructions to remove the product from the business system company before trying to move to Noah System
  • If it is a functioning Noah 4 that is being updated, uninstall Noah from Add Remove programs and reinstall the latest Noah 4 version. There have been rare cases where Noah Engine remnants have been left behind even with a functioning Noah System
  • If it is an upgrade from Noah 3, there may be some registry entries from an old business system on the machine. First, if present, uninstall Noah Engine from Add Remove Programs. If the Noah 4 installation gives the same error message, then delete the following registry keys if present:

NoahEngine1 key => HKEY_LOCAL_MACHINE\\SOFTWARE\\WOW6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\{27bca834-623c-4704-8ca5-ce2497347D72}
NoahEngine2 key => HKEY_LOCAL_MACHINE\\SOFTWARE\\WOW6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\{3E920E17-626C-486F-9338-C7D4EF170409}