Answer
This question was answered on June 13, 2004.
Much of the information contained herein may have changed since posting.
What Is the Osa.exe File?
The Office Startup Assistant (Osa.exe or OSA) is a program that improves the performance of Office XP programs. Office Setup places a shortcut to the Osa.exe file in the Windows Startup folder; the file is named "Microsoft Office".
What Does the Osa.exe File Do?
The Osa.exe file does the following:
Initializes automation.
Initializes some of the common fonts installed by Office XP.
Handles certain commands (New Office Document, Open Office Document, Help, and Screen Saver) on the Start menu and on the Office Shortcut Bar.
Displays Microsoft Outlook notifications when the Office Assistant is available.
What Are the Advantages of Running the Osa.exe File?
The Osa.exe file initializes the shared code that is used by the Office XP programs. When you use the Osa.exe file to initialize shared code, the Office XP programs start faster. If the Office programs, instead of Osa.exe, initialize the shared code, the programs take longer to start.
Can I Remove the Osa.exe File?
You can safely remove the Osa.exe file without causing the Office XP programs to fail. However, if you remove Osa.exe, you no longer benefit from the performance advantages that are provided by running Osa.exe. Also, the Office Shortcut Bar (OSB) may no longer start automatically, if you configured the OSB to start when Windows starts. (See the notes for the command-line switches later in this article.)
Additional Information
You can use the following command-line switches with OSA.exe:
-b
This switch starts the Office Shortcut Bar when it is used with the "-l" switch.*
-f
This switch opens the Open Office Document dialog box at startup.
-n
This switch opens the New Office Document dialog box at startup.
-s
This switch starts the specified screen saver at startup. Note that if there is no screen saver selected under Display in Control Panel, you receive a message stating this.
-o
This switch starts the Office Shortcut Bar.
*Osa.exe starts the OSB if the following registry setting is present:
Registry Path: HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Shortcut Bar
Name: AutoStart
Value: 1
Type: DWORD
Registry Path: HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Osa\Autostart
Name: NotFindFast
Value: 1
Type: DWORD
Typically, when Osa.exe is present in the Startup folder, it has the -b and -l switches set (Osa.exe -b -l).