I've searched everywhere, including the help in windows 7 (when you click F1).
I need a keyboard shortcut for increasing and decreasing volume, and I don't mean when playing a video or something, I mean the "general" one.
Windows Vista and Windows 7 do allow users to create keyboard shortcuts, unfortunately, not for volume control.
You actually have 3 choices;
1. Purchase a Multimedia Keyboard with built-in Volume Control buttons, usually around $20.
2. Download and install 3RVX, which is a skinnable freeware volume control application. Just Google 3RVX.
3. This one I have not tried, but it's a script someone came up with to use your Page Up/Down keys to control volume globally. If you decide to go this route, do so at your own risk and create a Restore Point and/or Back-Up your System.
The script with instructions can be found here: keyboard shortcuts - How to control master volume in Windows 7? - Super User