HOW TO: Identify a 16-bit Program in Windows XP

This step-by-step article describes how to identify a 16-bit program in Microsoft Windows XP.

Most Windows 16-bit programs run without problems in Microsoft Windows XP and it is frequently difficult to tell whether a program is 16-bit or 32-bit. Many users (and many administrators) do not know that the program is a 16-bit application.

However, a 16-bit program can cause minor problems that may affect the performance level of the computer or the functions of the program itself. Because of this, you may need to determine whether the program that has a problem is a 16-bit program.

Identify a 16-bit Program

To identify a 16-bit program:

1. Use Windows Explorer to open the folder that contains the program's executable (.exe) file.
2. Right-click the .exe file, and then click Properties.
3. A 16-bit program does not have a Version tab in this dialog box.

Identify 16-bit Programs that Are Running

To determine if any 16-bit programs are currently running, and identify any that are:

1. Start Task Manager. To do so, right-click a blank spot on the taskbar, and click Task Manager.
2. On the Processes tab, note the contents of the Image Name column.
3. If any 16-bit programs are running, you see an entry for Ntvdm.exe, which is the virtual DOS machine that is provided by Windows XP. You also see wowexec.exe (the Windows on Windows subsystem), and the executable name of each 16-bit program that is running in that WOW virtual machine. As a helpful visual aid, wowexec.exe and the 16-bit executable file names are indented.

For additional information about how to identify and troubleshoot 16-bit programs in Windows XP, click the article number below to view the article in the Microsoft Knowledge Base: