How to: Debug 64-Bit Applications

How to: Debug 64-Bit Applications


You can debug a 64-bit application that is running on the local computer or on a remote computer.

If you are debugging locally, Visual Studio runs under WOW64, the 32-bit x86 emulator that allows 32-bit Windows applications to run on 64-bit Windows. Local debugging under WOW64 is supported on x64 only.

If you are debugging remotely, Visual Studio can run under WOW64 or on a 32-bit computer. You can debug x64 applications, in addition to 32-bit applications that are running under x64 WOW mode or on 32-bit operating systems.

To debug a 64-bit application that is running on a remote computer, you need to install the 64-bit remote debugger on the remote computer. For more information, see Remote Debugging.

If you debug a 64-bit application on the local computer, Visual Studio uses remote debugging to connect between WOW64 and the 64-bit application on the same computer. The remote debugging components will be installed automatically when you install Visual Studio on the computer.

In either case, installing remote debugging on a 64-bit computer installs both the 32-bit and the 64-bit versions of the Remote Debugging Monitor. To debug a 64-bit application, you must use the correct version, which is Remote Debugger (x64) on the Start menu. For information about how to install 64-bit remote debugging components, see Remote Debugging.

Debugging 64-bit code is almost identical to debugging 32-bit code. One difference is that Edit and Continue is not available for 64-bit code.

Mixed-mode debugging (calls from native code to managed code, or vice versa) is supported for x64 processes, if the managed code uses Microsoft .NET Framework version 4 or later.

Mixed-mode debugging is not supported for x64 processes that use .NET Framework versions earlier than 4.0.

To start the 64-bit Remote Debugging Monitor

  1. Click Start, point to All Apps, open the Visual Studio  version folder, and then choose the Remote Debugger Folder. In the File Explorer window, open x64 and then launch msvsmon.exe.


    From the Windows Command Prompt, run \Program Files[ (x86)]\Microsoft Visual Studio version\Common7\IDE\Remote Debugger\x64\msvsmon.exe.

  2. Configure the Remote Debugging Monitor for remote debugging. For more information, see Remote Debugging.

© 2015 Microsoft