HelpHost.exe is the executable binary file of "Microsoft Help Center Hosting Server" program, which is part of the "Help and Support Center" application on your Windows system.

If you are using Windows XP, you can click the Start button and click the "Help and Support" on the start menu. The "Help and Support Center" window shows up. Now if you check the process list with Windows Task Manager, you will see 3 processes are started:

helpctr.exe    19,972K
HelpHost.exe    6,052K
HelpSvc.exe    10,396K

If check the file information of HelpHost.exe, you should see:

Directory: C:\windows\PCHealth\HelpCtr\Binaries
File name: HelpHost.exe
Description: Microsoft Help Center Hosting Server
Size: 102,400 bytes
Date: Monday, April 19, 2004, 1:28:12 PM
Version: 5.1.2600.0
Company name: Microsoft  
System essential: No
Virus/Spyware/Adware: No

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