Debug Ax Code in Visual Studio in Microsoft Dynamics AX 2012

The steps involved in in debugging AX code through Visual Studio :

Step 1: 

Make sure AOS Service runs on account which you logged in. 

Step 2:

Open visual studio and click on AX Application explorer (Shortcut Ctrl + D)AOT opens and you can browse nodes as you used to do in Dynamics AX.Open the object which you want to debug and insert breakpoint.

Step 3:

Then in Visual studio, Click on Debug->Attach process

Note: As shown in above image, First make sure two check boxes at bottom are marked.Then only you can find and able to select AX32Serv.exe (AOS)  process and click on attach button.

Step 4:

You done with setting up visual studio to debug code running in CIL.
Now restrart process in Dynamics AX which you want to debug and you can find Visual studio debugger opened for you.