Nscp.exe command can't be foud

Dear Icinga Comunity,

I have installed the Icinga Agent with the nsclient++ on my windows Servers. To monitor processes and memory i use the scp.exe. On some server’s i can’t monitor the processes because the scp.exe can’t be found. I tried the troubleshooting guide example:
C:\Program Files\ICINGA2\sbin\icinga2.exe variable get NscpPath
and the path variable is empty: But this variable is empty on every Server System and on some it works and some not. The only difference, the installations are all the same, i can find when i use inspect on the ICINGA Director:

On a non working scp.exe the executed command looks like this:
‘\nscp.exe’ ‘client’ ‘–critical’ ‘free < 10’ ‘–log’ ‘critical’ ‘–module’ ‘CheckSystem’ ‘–type=physical’ ‘–warning’ ‘free < 20’ ‘-b’ ‘-q’ ‘check_memory’

On a working system the executed comman looks like this:
‘C:\Program Files\NSClient++\nscp.exe’ ‘client’ ‘–critical’ ‘free < 10’ ‘–log’ ‘critical’ ‘–module’ ‘CheckSystem’ ‘–type=physical’ ‘–warning’ ‘free < 20’ ‘-b’ ‘-q’ ‘check_memory’

How can i use the full path?

*Name : icinga2
Architektur : x86_64
Version : 2.12.3
Ausgabe : 1.el7.icinga

Thank you!!!