spools.exe definition, relationships, removal:

The spools.exe file is installed and used by Win-Spy. This process silently works in background and performs harmful actions. It remains active while spools.exe is present in the system. Removing the file will immediately terminate spools.exe and prevent it from running later.

That is why you have to delete the spools.exe file. If you cannot erase it, consider using recommended spyware removers, which will get rid of spools.exe and associated parasites for you. If you are in doubt, please scan the spools.exe file using you regular spyware remover or antivirus program.