I know there are various questions and books on this but I can\'t seem to get my C++ DLL injected into any processes.
The code to inject the DLL:
#in
I would start with someone else's working example and go from there. The example projects, tutorials, and explanations on CodeProject are really solid.
Here is one on Hooking and DLLs.
And another. And a google search for you.
For certain kinds of hooks, there are permission limitations that you have to overcome, or you have to accept the fact that you can't hook every process.
Setting the UI-Access to true, and having your executable in C:/Program Files/, and having your dll digitally signed helps to access some of the secure windows in Windows. Here is an article that discusses some of these things.
Hope that helps.