This is originally from Sara's blog.
It also works with almost any version of Visual Studio, you just need to change the "8.0" in the registry key to the appropriate version number for your version of Visual Studio.
The guide line shows up in the Output window too. (Visual Studio 2010 corrects this, and the line only shows up in the code editor window.)
You can also have the guide in multiple columns by listing more than one number after the color specifier:
RGB(230,230,230), 4, 80
Puts a white line at column 4 and column 80. This should be the value of a string value Guides in "Text Editor" key (see bellow).
Be sure to pick a line color that will be visisble on your background. This color won't show up on the default background color in VS. This is the value for a light grey: RGB(221, 221, 221).
Here are the registry keys that I know of:
Visual Studio 2010: HKCU\Software\Microsoft\VisualStudio\10.0\Text Editor
Visual Studio 2008: HKCU\Software\Microsoft\VisualStudio\9.0\Text Editor
Visual Studio 2005: HKCU\Software\Microsoft\VisualStudio\8.0\Text Editor
Visual Studio 2003: HKCU\Software\Microsoft\VisualStudio\7.1\Text Editor
For those running Visual Studio 2010, you may want to install the following extensions rather than changing the registry yourself:
These are also part of the Productivity Power Tools, which includes many other very useful extensions.
Start debugging, as soon as you've arrived at a breakpoint or used Debug > Break All, use Debug > Windows > Modules. You'll see a list of all the assemblies that are loaded into the process. Locate the one you want to get debug info for. Right-click it and select Symbol Load Information. You'll get a dialog that lists all the directories where it looked for the .pdb file for the assembly. Verify that list against the actual .pdb location. Make sure it doesn't find an old one.
In normal projects, the assembly and its .pdb file should always have been copied by the IDE into the same folder as your .exe, i.e. the bin\Debug folder of your project. Make sure you remove one from the GAC if you've been playing with it.
Best Answer
I found the solution from here:
And it worked for me.