So I solved it by myself.
If someone have to handle this problem and can't find a solution by using google too, I hope this description will help you.
The problem is described as the following.
By opening the sdk-manager a cmd-console shows up for a moment and nothing happens.
The problem can be solved by editing the android.bat. You found it in your tools folder.
There you will find the following lines:
set java_exe= call lib\find_java.bat if not defined java_exe goto :EOF
Here you define the path for java_exe here. So replace this with for example:
set java_exe=D:\java\jre8\bin\java.exe
After you did that have a look at this line:
for /f "delims=" %%a in ('"%java_exe%" -jar lib\archquery.jar')
do set swt_path=lib\%%a
The Windows cmd is not able to invoke the command inside of the bracktes.
I don't know why. If anybody knows, please write a comment.
There you have to replace the code inside of the bracket with: x86_64
for /f "delims=" %%a in ("x86_64")
do set swt_path=lib\%%a
In the last step you have to add a path-variable called ANDROID_SWT which links to folder lib\x86_64 inside of the current folder. For example:
D:\Android\tools\lib\x86_64
Then run the android.bat and the SDK-Manager will be shown up.
