What is Osa.exe – Is it an Essential or Useless Process?

According to Microsoft, osa.exe (also referred as Microsoft Office Startup Assistant Shortcut) is used for launching Microsoft Office programs faster.

Microsoft claims that this process helps in the quick launch of Office applications by:

  • Initializing automation
  • Initializing common fonts
  • Handling certain commands, such as Screen Saver, New Office Document, Help, and Open Office Document.
  • Displaying notifications for Microsoft Outlook.

While Microsoft claims osa.exe to be a helpful process, a lot of Windows users claim that this process is not only useless, but it also causes frequent computer freeze ups by consuming a large amount of system resources.

To understand this process better, the issues surrounding it and their resolution methods, we will discuss the following topics in this article:

  • Advantages of using this process.
  • How to run this process when you start Windows in case the process is disabled at startup.
  • Command-line switches you can use with osa.exe.
  • Issues surrounding this process and their resolution.


The advantage of using this process, according to Microsoft, is that it helps Office programs start faster. If you remove this process, your office programs may take more time to launch.

By default, the process starts automatically everytime you boot Windows. In case the process is not listed in your startup sequence, you can perform the following steps to run the file when you Start Windows.

  1. Close all Windows Programs.
  2. Open Windows Explorer.
  3. Browse to the following folder:
  4. For Microsoft Office 2007 – C:\Program Files\Microsoft Office\Office12

    For Microsoft Office 2003 – C:\Program Files\Microsoft Office\Office11

  5. Right-click and drag the osa.exe file to the C:\Documents and Settings\username\Start Menu\Programs\Startup folder.
  6. Click Create Shortcut Here.

Command-Line Switches

The osa.exe utility lets you run a number of system shortcuts directly from a command line prompt. For instance, you can type a keyboard key combination into this utility to immediately load your current screen saver. Before we learn how to do this, let’s have a look at the different command-line switches that you can use with this utility.

Switches Description
-f Used for launching the Open Office Document dialog box at startup
-s Used for loading the specified screen saver at startup
-n Used for launching the New Office Document dialog box at startup
-o Used for starting the Office Shortcut Bar
-b When used with “-I” switch it launches the Office Shortcut bar

Now, let’s see how you can use -s switch for launching specified screen saver.

  1. Click Start.
  2. Click Run.
  3. Type osa.exe in the Open box, and then press Enter.
  4. Type -s and then press Enter.

You can also use other switches the same way – only replace -s with the switch you want to use in Step 4.


The most fierce and consistent complaint about this process is that it often reports high CPU usage without any reason. Many Windows users complain that the process causes frequent system freeze ups.

If you too are facing such issues, you can safely remove the process from your startup sequence. No tangible drop in the loading speed of Office programs was noticed by users who removed this process from their Windows Startup menu.

Here are the steps you need to follow in order to remove the process from your startup sequence:

  1. Click Start.
  2. Click Run.
  3. Type msconfig and press Enter.
  4. Click Startup.
  5. Uncheck the checkbox before Office Startup Assistant.
  6. Click Apply to save your changes, and then click OK.