QA: MSI Interview: What is the difference between installations using ALLUSERS="", ALLUSERS=1 and ALLUSERS=2 option?

Q: What is the difference between installations using ALLUSERS=””, ALLUSERS=1 and ALLUSERS=2 option?

ANS:

1. ALLUSERS=””: It specifies per-user installation context


2. ALLUSERS=1: It specifies per-machine installation context


3. ALLUSERS=2: It enables the system to define the values of ALLUSERS, and in turn the installation context, dependent upon the user’s privileges and the version of Windows

1. Windows 7: Uses the MSIINSTALLPERUSER property to specify the installation context.

i. MSIINSTALLPERUSER ="": Per-Machine installation.

ii. MSIINSTALLPERUSER =1: Per-User installation

2. Windows Vista: Windows Installer complies with User Account Control (UAC). If the user has user access privileges, and ALLUSERS=2, the installer performs a per-machine installation only if Admin credentials are provided to the UAC dialog box. If UAC is enabled and the correct Admin credentials are not provided, the installation fails with an error stating that administrator privileges are required. If UAC is disabled by the registry key, group policy, or the control panel, the UAC dialog box is not displayed and the installation fails with an error stating that administrator privileges are required.


3. Windows XP: Set Windows Installer performs a per-user installation if the user has user access privileges.


4. Windows 2000: Windows Installer performs a per-machine installation if the user has administrative access privileges on the computer. If the user does not have administrative access privileges, Windows Installer resets the value of the ALLUSERS property to an empty string ("") and performs a per-user installation.