The Lotus Notes installation program cannot upgrade from single user to multi-user. However, you can use a manual procedure to upgrade a single user install to a higher version multi-user install and also move the user's data directory and other content to new install directories.
For related information, see Configuring custom data directories for multi-user install or upgrade on Windows or Citrix
in Domino Administrator help.
1. Log in as an administrative user or user with elevated privileges.
2. Back up the user's data directory (by default located below the Notes install directory, for example C:\Program Files\IBM\Lotus\Notes\data).
3. Back up the user's NOTES.INI file (by default located in the Notes install directory, for example C:\Program Files\IBM\Lotus\Notes).
4. Back up any third-party binaries installed in the Notes binary directory. This step is optional if there are no binaries or if it would be easier to reinstall them.
5. Uninstall Notes using the Notes uninstall procedure.
6. Install Notes and when prompted choose a multi-user install.
Note: The Notes-only install kit supports multi-user install; the Allclient install kit does not.
Note: The multi-user install creates a shared data directory under, by default, C:\ProgramData, which contains database templates and other shared data files. This directory is read-only for non-administrative users.
7. Start Notes as the current (administrative) user and respond to all setup prompts.
8. Merge the old NOTES.INI from the backup with the newly installed NOTES.INI to preserve preferences and activate any third-party code.
9. Merge the old data directory from the backup with the newly installed data directory. The merge will depend on the versions of the Notes single-user install and multi-user install.