To install MIS Communicator as a service the wright way you must folow the steps below.
First you need to run MISCommunicatorInterface.exe as administrator and you should alter the EXE definitions to run as administrator.
Right click the file and chooser Properties:
After running the engine open the Advances Options and choose the option Install Service (You can change the name of the service):
After this steps you already installed the service, but if you are on a server you must attach the service to an administrator user or else will give you some permission problems in the future.
Open the services management console:
On the list find your service, right click it and choose Properties
On the option shown below instead of Local User choose This Account ans use the credentials of an Administrator.