@echo off
C:\Eigene Dateien\POCSAG\POC32\fmsbeep.exe "C:\Eigene Dateien\POCSAG\POC32\alarm.wav" "ALARM" "10000" "33023" "65535" "MS Sans Serif" "45" "255"

Probiers mal so.

Ansonsten:
@echo off
C:\Eigene~1\POCSAG\POC32\fmsbeep.exe "C:\Eigene~1\POCSAG\POC32\alarm.wav" "ALARM" "10000" "33023" "65535" "MS Sans Serif" "45" "255"