Before installing the service, think very hard as to whether this is the way to go for you, as it adds a lot of extra configuration steps. In most cases it is unnecessary to install pdfServMachine as a service.
1. Download
Down and unzip the SDK to a suitable directory.
e.g. c:\pdfServMachine
2. Install the service
From the command line, run:
pdfServMachine /Service
3. Set the logon account for the service
Run the services applet.
Launch the services applet. e.g. Start->run then type:
services.msc
Select the pdfServMachine from the list of services.

Double click on the service, then switch to the logon tab.
Select "This Account" and enter in a user with Administrator rights.
Click OK.

4. Configure security with dcomcnfg.exe
e.g. Start->run then type:
dcomcnfg
Find the pdfServMachine entry, as shown below.

Right click on the pdfSerMachine icon, select Properties, then select the "Security" tab, as shown below.
Edit the "Access Permissions" to include the user account or group that matches the account the service will be run under. Apply the changes and exit dcomcnfg.
5. Start the service.
From within the services.msc view, optionally set the "start up" type of the service to Automatic, then start the service.