NTP for Windows Installation Problems

The NTP installer for Windows eventually creates a hidden user with the name ntp, and the NTP service (ntpd) is then configured to run under this user account.

When the ntp user is created then a password has to be specified for this user to be able to start the service automatically.

If the NTP software package is upgraded then the installer is unable to retrieve the current password for the existing ntp user, so the administrator who installs the new NTP package has to specify the ntp user's password once more during installation. If then a password is entered which doesn't match the existing password then the NTP service fails to start.

If the administrator has forgotten the ntp user's password he can

• delete the existing user via the Windows account manager, run in extended mode, so a new user is created when the NTP installer is run later, with the new password given during installation
• change the existing ntp user's password from within a command line window, so the user's password matches again the password specified during installation of the upgrade

To change the existing ntp user's password with a simple command you can open a command line window with elevated permissions (cmd.exe, “Run As Administrator …”), and run the following command:

net user ntp new_passwd

where new_passwd has to be replaced by the real password.

Please note that newer Windows versions only accept passwords that meet specific requirements, e.g. a minimal length, and a combination of upper case and lower case characters as well as numbers.

If a required DLL is missing on the Windows system then the Windows service control manager is unable to start the NTP service.

To see if this is the case you can run the command ntpd -n from within a command line window. If a DLL is missing then an appropriate popup window appears when this command is executed.

A DLL which can possibly be missing is the runtime library of the VS2008 compiler which has been used to build the NTP package.

Normally the VS2008 runtime library should be shipped with and installed with any Windows version released after the VS2008 compiler package, including all Windows 7 versions. So usually this only needs to be explicitly installed on older Windows versions.

The executable files provided by the NTP software package are 32 bit only, so the 32 bit version of VS2008 runtime library has to be installed, even on 64 bit Windows versions. If the runtime library is missing, it can be downloaded here:
http://www.microsoft.com/en-us/download/details.aspx?id=29

An appropriate hint is also shown on the Meinberg NTP download page:
http://www.meinbergglobal.com/english/sw/ntp.htm#ntp_stable

— Martin Burnicki 2019-06-06