Emulated device not working - Error: "AVD Manager - Unable to locate adb"

When I try to start a virtual Android device via AVD Manager the error "AVD Manager - Unable to locate adb" pops up. OS is Windows 10.

* SDK platforms level 23-30 are properly installed via Android Studio

* Because of umlauts in the user folder I had to place the Android SDK somwhere else ( C:\Android\Sdk )

* Evironment variable "ANDROID_SDK_ROOT" is poiting to C:\Android\Sdk

* SDK Tools are installed properly and mentioned (platforms, platform-tools and tools folder) in PATH variable 

** Android SDK Build-Tools, Android SDK Command-line Tools (latest), Android Emulator, Android SDK Platform-Tools and Google Web Driver are installed

** adb.exe is working no problem when called via command line interface, still AVD Manager is unable to locate it

* File -> Project Structure -> SDK Location -> "Android SDK Location" points to C:\Android\Sdk

So I don't understand why emulated devices refuse to work on my local machine. Any ideas?