Copy-paste when possible, but watch for hidden spaces. If typing manually, use a text editor first to verify.
Moreover, many city bus simulators are used in: Copy-paste when possible, but watch for hidden spaces
If you're encountering issues during the activation process, don't worry. Here are some common problems and their solutions: Copy-paste when possible
If your simulator still shows the classic "to activate the city bus simulator please insert the serial key and your name" box every time you launch, check for an official patch. The developer may have released a smoother system. Copy-paste when possible, but watch for hidden spaces