Irrational wrong disc problem

[Wolak]

I have installed M2TW, then Kingdoms 1.5 and then SS6.3 and SS6.4. Now, trying to launch both Kingdoms (from kingdoms.exe on my hard drive, or from kingdoms.exe or Launch.exe on Kingdoms CD) or SS6.4 I receive message

"Wrong disc inserted.
Please insert the original "Kingdoms" CD/DVD.
Please have a look at http://www.securom.com/message.asp?m=wrongdisc for further, more detailed information."

despite having original Kingdoms CD in.

I use Windows 7. I disabled UAC. I first installed everything in C:\Program Files but then moved it to a new folder.
I also do not find file launcher.exe anywhere, though in many guides it is mentioned as placed in M2TW folder (I have only kingdoms.exe and medieval2.exe there).
Steam has been detected on my computer but I do not use it, it is actually uninstall and SS must has detected some remnants which I actually found scattered here and there in some folders.

[Navajo Joe]

Go into MTW2/Mods/6.3, find SS Set Up, select, right click and Run as Admin