How it's all done
All the registry keys that we are going to use are stored under HKEY_CLASSES_ROOT. It stores them in this form:
- Every file extension is given a key. This key will be exactly the same as the file extension including the dot (eg:
HKEY_CLASSES_ROOT\.bmp).
- This key’s "default" value refers to an application’s registry key:
- Every application is given a key (or a group of keys if the program is associated with multiple file types). This is not necessarily the same as its “EXE name”, but in this key, among other things, there is a value that contains the location of the default file icon for this file type. For example: a “.frm” file. You should recognise this as a VB form.
This is what my registry has to say about a “.frm”:
Your registry may differ, but the format should still be
the same. The important thing to notice is how we got from “.frm” to “C:\program
files\Microsoft Visual Studio\VB98\vb6.exe,1”