Although I wrote the following procedure in 1999, it should work for you, possibly with minor modifications:
This is the procedure for Setting Up Multiple Users on a Single PC. Modified from the instructions offered in the Lotus Help Desk Support for Notes manual.
1. Install Notes client software with the program files in their normal location (i.e. c:\notes) but designate each user's data directory below the c:\notes\data directory (i.e. c:\notes\data\user1data, c:\notes\data\user2data, and so on).
2. Use Windows Explorer, find and move the NOTES.INI file to the new user's data directory.
3. Using Windows Explorer, find the NOTES.EXE file and create a Shortcut.
4. Drag the shortcut to your Windows desktop and rename it with the user's name (i.e. User1 NOTES).
5. With the shortcut icon selected, choose File, Properties.
6. In the Start in: field, enter the path of the directory created for the user (i.e. c:\notes\data\user1data).
7. Start Notes and setup the workstation for the first user.
8. Repeat steps 1 to 7 reinstalling Notes for each user. This will install the software again, designating a different data directory for each user (i.e.. c:\notes\data\user2data).
The key points to remember when setting up multiple users are:
Move the NOTES.INI file into the new user's data directory.
Indicate the user's data directory in the shortcut's properties.
If you follow these instructions, each user will have his or her own distinct desktop (DESKTOP.DSK) and user preferences (NOTES.INI)