SQLEXPR.EXE vs SQLEXPR32.EXE
In case you've installed SQL Server Express and found out that there are two executables for installation (for example when installing SSE bundled with VS2005) SQLEXPR.EXE and .SQLEXPR32.EXE, you might have wondered what's the difference.
From: http://msdn2.microsoft.com/en-us/library/ms143680
SQL Server Express Install Packages
There are two executables available to install SQL Server Express:
- SQLEXPR.EXE. Installs both on x86-based computers and on the 32-bit subsystem (WOW64).
- SQLEXPR32.EXE. Install on x86-based computers only. This program will not run at all on IA64, and it will run as a 32-bit application on x64-based computers.