It resets the activation timer (grace period) for Office, allowing users to extend the trial or re-arm volume licenses (e.g., in a KMS setup).
OSPPREARM.EXE is automatically installed when you install: ospprearmexe download verified
ospprearm.exe depends on numerous other system files within the Microsoft Office installation structure to work properly. A single .exe file downloaded from the internet will likely not work. It resets the activation timer (grace period) for