I ran a system scan with Grindinsoft Trojan Killer V2.0.6.7 and got a hit on:

Steam\steamapps\common\the settlers 7 paths to a kingdom\redist\drivers\vcredist_x86.exe

According to the Trojan Killer it was infected with a trojan.win32.pasta.gbz. I have no idea what this trojan does or what it targets but i removed the file just in case.