The Parsec service lets Parsec restart itself with administrator privileges in order to pass inputs and capture anything with elevated permissions, such as the task manager, Windows' lock screen, User Access Control (UAC) and any programs running as admin.
Without it, in some cases, the people connected might not be able to control anything, some applications might not show up in Arcade and Approved apps, and Parsec might fail to capture the display and disconnect people with error 14003.
Checking if Parsec service is running correctly
On the host, press Ctrl+Shift+Esc to open task manager, and find both parsecd.exe and pservice.exe in the Details tab.
Both should be there, running with the username SYSTEM. If that's not the case for you, do the steps below to fix it.
Fixing Parsec service
The following should be done on the host PC:
- Press Windows key + R, type services.msc and press Enter.
- Find Parsec, and double-click it. (can't find it? If you're using portable Parsec, run it as admin instead. If not, reinstall Parsec)
- Set Startup type to Automatic
- Click the Start button. If the button is grayed out, you should instead click Stop then Start
- Click OK to close
- Right-click Parsec in the tray bar and click Restart