SYSTEM: Win7 64 bit, 16GB RAM.
ISSUE
Whenever I try to launch multiplayer (from either the desktop shortcut or from Single Player), the game crashes. The little desktop window launcher thing appears, and immediately "DCS has stopped working". Attempting to wait for it to sort itself out results in "DCS has stopped working. A problem has caused the program to stop working correctly. Windows will close the program and notify you if a solution is available."
I am able to launch in single player mode. However, as stated, attempting to go to multiplayer from single player does not get around this issue.
I am also unable to attempt single player missions - they also instant crash on launch, in exactly the same way (as far as I can tell) as multiplayer.
I previously had DCS World and the A-10 module installed. This had the same issue. I deleted everything and reinstalled sans-A-10, and still had the same issue.
When the A-10 module was installed, at no point was I asked for a CD key.
Prior to finding out I needed DCS World, I had A-10 partially downloaded from Steam (about 800MB of it) - deleted the contents of the Steam folder regarding A-10, unsure if it's left registry files or something. I never launched it. I'm not good with computers.
SUMMARY
Crash on loading multiplayer
Crash on loading mission
Not asked for registration at any point
EDIT: When I install, it complains about C++...
"Setup has detected that this computer does not meet the requirements to install this software. The following blocking issues must be resolved before you can install Microsoft Visual C++ 2010 x86 Redistributable Setup software package. A newer version of Microsoft Visual C++ 2010 Redistributable has been detected on the machine."
Attempting to rollback to a different version of C++ by downloading results in the same issue.
EDIT 2: Someone suggested that I check the DCS Protect thing, I got this error: