Frequently Asked Questions

Q Why are there 2 versions of Tardis?
A The Windows NT/2000/XP/2003 version (Tardis 2000 NT Service) runs as a service so it is still working when nobody is logged in, important for Server machines that may be logged off but are being used as servers. The other version is for Windows 95/98//ME/2000/NT/XP/2003 where Tardis is run as a normal application.
Q Who is Tardis 2000 for?
A Tardis is designed to be used by almost anyone. It is for dialup users and LAN users.
Q Why is it called Tardis 2000?
A Tardis is a time machine that appeared on BBC TV's Dr. Who program. The 2000 has been added, not to indicate Year 2000 compliance (Tardis has always been compliant), but to indicate that it is a complete rewrite i.e. not just the next version of Tardis95/NT.
Q Where do I find the latest version of Tardis?
A Visit the Tardis home page
Q I bought Tardis for Windows 3.x/ Tardis for Windows 95/ Tardis for Windows NT some time ago. I now want to migrate to Tardis 2000, do I have to register and pay again?
A If you purchased any of the previous versions of Tardis an additional registration is required and the full Tardis 2000 registration fees apply.
Q What is NTP?
A NTP is an Internet protocol for time synchronization. For details on it look at on the World Wide Web.
Q What is broadcast NTP?
A NTP includes an option to broadcast a timesignal.
Q My LAN has no broadcast NTP, how do I set it up?
A One way to do the job is to get a copy of XNTP, this is an implementation of NTP that supports many machine types (mostly Unix machines although there is a port to NT). See the NTP home web site Tardis will also run in a time server mode where it will broadcast the time from the PC on which it is run.
Q Why are only some of the PCs being updated when I use broadcasts?
A Time broadcasts are limited to the local subnet, make sure that Tardis is set up to broadcast to all the required subnets or use multicasts.
Q Year 2000 compliance
A Tardis is and always has been Y2K compliant. It does rely on the underlying operating system for some services and the hardware clock of course so if there is a problem with Windows or the PC's bios then Tardis may not be able to correct it. Tardis does not hold dates in yy/mm/dd form internally so Y2K should not be an issue. Tardis uses Unix standard time representations internally (i.e. time is held as number of seconds since 1970). I recommend that you verify for yourself that Tardis is Y2K compliant as a final check that it is suitable for your purposes.
Q Can I use Tardis with ntp/xntp?
A Yes, you can use Tardis as a server for xntp clients or visa versa.
Q How do I set up Tardis as a server?
A Tardis can both act as a server for other time clients. Tardis is set up to always act as a server. You don't need to do anything but run it. Both clients and server machines need to have TCP/IP installed. On client machines set the hostname or IP address ( something like of the server as the source of time information. You can even set Tardis to use itself as a server by setting the time source as localhost or Not very useful but it does demonstrate the technique. When the client accesses the server the relevant service indicator on the server's dialog should blink RED to show that the server is being accessed. (Not on the Service version)
Q Can I use Tardis when I have a firewall with a proxy server that blocks NTP?
A Yes, use the HTTP protocol.
Q Does Tardis support Mac, OS/2, Novell, DOS, etc.
A No.
Q Tardis doesnít seem to handle daylight/summer time in Europe?

The windows Date/Time control panel must be set to the correct timezone for your machine for Tardis to work properly. Make sure that this is correct. If Tardis is still setting the time wrongly it could be that Windows 95/98/ME's rules are wrong for your timezone. The following Windows 95/98/ME timezone rules are known to be wrong. Some parts of Australia Russia Europe (rules changed in 1996) To fix the rules get hold of the Microsoft kernel toys and use the timezone editor to correct them.

Q Where can I get NTP for UNIX?
Q The NT/2000/XP/2003 service version doesnít update the clock when nobody is logged in?
A Use the setting->control panel->services to edit Tardisís startup settings. Set the Tardis service to run under the ĎAdministratorí account
Q Tardis goes through the whole list of time servers without stopping
A Make sure that you don't have the 'automatically change server on success' option set. This option is used the quickly scan through the server list. It shouldn't be used for normal operation.
Q I canít tell what the Tardis 2000 service is doing

Try running tardisnt from the command line so you can see what is going on in real time.

First , stop the service.

Then start a command prompt. Type

tardisnt debug

This will start the service in debug mode. It can be stopped with control-c.

Q I want to disable Tardisís time services

You can disable some of the Tardis time services but not the NTP service. It is too closely linked to the client side. From the start menu select 'run'. Type 'regedit' in the box and hit return.

You should see a thing rather like the explorer start.

Follow the folders down like you would in explorer to get to the HKEY_CURRENT_USER\Software\Tardis\ folder

you should see a list of keys on the right side now.

Add keys as follows they are all of type DWORD.

UDPServer 0 TCPServer 0 867UDPServer 0 867TCPServer 0

Now shut down the regedit program and run tardis. All should be well.

This is for Tardis 2000 for 95/98/ME. The same applies to Tardis 2000 NT Service but the keys are in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tardis\Parameters\

Q Tardis 2000 may give error 87 messages after being able to sync one time.

This can be fixed as follows.

Win95 comes with Winsock 1, Tardis2000 requires Winsock 2, which can be downloaded free from Microsoft's Web site.

To get Winsock 2, go to Microsoft's Windows Update web page (a menu item in IE 5.5's "tools" menu) and do a search for Winsock 2.

Microsoft recommends that you also install a Y2K fix after installing either Winsock 2 or DUN 1.3.

The link for that is right there on the Winsock 2 page, as are the instructions for downloading & installing.

Q Tardis starts then immediately disappears
A The 'How often the time is set' setting can be set to tell Tardis to exit once it has corrected the time by sliding the control all the way to the left.

Once this has been set you may not be able to change the setting because Tardis will set the time and terminate before you get the chance. If this happens then hold done the SHIFT key then start Tardis. This will prevent it terminating.

Q What is the format of the import/export file

The import/export file format is pretty simple. One line per server. The fields are separated by | characters.

field 1 is the name field 2 is the address field 3 is the protocol (0-9) field 4 is whether a proxy server is used (for HTTP) field 5 is whether unsynchronized NTP should be rejected (SNTP)


Q Tardis canít get the time from internet time servers

Firewalls or proxy servers will block most of the time protocols that Tardis uses. The one that might work is the HTTP protocol.

Another possibility is to open your firewall/proxy tcp port 37 and use the RFC868/tcp protocol.

Q Tardis doesnít send from port udp/123, which means my firewall doesnít allow the responses through/generates bogus virus warnings.

By default Tardis SENDs to port 123 but the SOURCE port it uses is allocated by the system so the responses come in on a different port number. There is a tweak in the registry you can make to force Tardis to lock the source port to 123.

the key to add is HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tardis\Parameters\SNTPFix it is a DWORD and should be set to 1

The same applies to Tardis 2000 but the key is HKEY_CURRENT_USER\Software\Tardis\SNTPFix

Q I want Tardis to set the time at an exact time of day.
A The best way to do this it to use the non-service version of Tardis and run it so that it terminates after getting the time. You then run Tardis at the time you want using the NT AT command or win 95/98's task scheduler.
Q Tardis doesnít synchronize with my GPS/Radio clock.

Tardis may not synchronize with a GPS source for various reasons.

Tardis may not see the NMEA messages because the wrong serial port is being used or the baud rate is incorrect.

If it is seeing messages but isn't synchronizing it is probably because the GPS device hasn't had sufficient time to see enough satellites to synchronize.

Before Tardis 2000 V1.3 the GPS device was required to send a message every second. Some GPS devices don't do this.

Q Where are the license keys?

The reason we don't have license keys is as follows.

Some of the most annoying things about shareware are the crippled and/or time limited demos that are normally available. As soon as I get one of these I usually don't get much further, I don't try the program and don't end up buying it. If we did have license keys there would be the problems of crackers creating their own, having to issue new ones for users who lost theirs. Tracking how many have been issued etc. etc.

We went for the friendliest, lowest cost way of doing things.

The downside is that fewer people pay. We will live with that to keep everyone's life simple. Anyway, most of the registrations come from companies that regularly audit their software to check if it has been paid for so our major customers sort of police themselves.

The opposite extreme to this kind of scheme is something like Windows XP's licensing. I can't begin to tell you how popular THAT is...

Q Where does the NT service log messages

Tardis 2000 NT Service logs events to the system event log. Use the event log viewer to view them.

Tardis logs messages under the 'application' section.

To control logging select the 'information' option page on the Tardis control panel and switch on or off the amount of logging you require.

Q My GPS time is a little off.

The problem comes from trying to get a GPS device to TELL you the accurate time.

NMEA supports several sentences that contain the time.

Tardis supports all of these and will use the best one it sees. $GPZDA is best because it is designed to tell the time.

The next best is $GPRMC. This tells you the time of the last position fix (which is usually in the last few seconds).

If your GPS only supports $GPRMC you should find that the offset is fairly constant. You can manually tell Tardis this offset as follows.

from the start menu select 'run'. Type 'regedit' in the box and hit return.

You should see a thing rather like the explorer start.

Follow the folders down like you would in explorer to get to the HKEY_CURRENT_USER\Software\Tardis\ folder

you should see a list of keys on the right side now.

Add a key called NMEAAdjust of type 'String'. This is the NEMA time offset in milliseconds.

Now shut down the regedit program and run tardis. All should be well.

This is for Tardis 95/98. The same applies to TardisNT but the key is


Q Tardis gets but doesnít set the time.

The problem might be the account that the tardis service is running under. When you run it under debug you are running it as 'you' and 'you' probably have administrator privileges. When it runs as a service it runs under the local SYSTEM account by default.

Use the services control panel to change this to 'administrator' and it should start working.


Q How does the service version differ from the application version?

The service version is a windows service that has a couple of differences to the application version.

Tardis is split into 2 parts, tardisnt.exe which is the service that actually does the time synching and tardis.cpl that is the control panel that presents the user interface. These 2 parts aren't connected in any way except by the settings in the registry. The control panel sets up the settings and the service uses them.

Tardisnt.exe is running so the service is install and running, you can use the control panel to start and stop the service but you won't see anything happening as such.

If you want all the normal feedback and the icon in the system tray etc. you CAN run the Application version of Tardis on NT/2000 too.

To check what the service is doing you can look in the eventlog under the application section or run it under debug mode from a command line prompt like so.

tardisnt debug

Remember to stop the service first before running it as debug.

Q Can I use w32time and Tardis on the same PC?

Tardis and w32time will not coexist on the same PC because they are both trying to do the same job using the same resources. In this case the resource is the udp port 123.

Actually, Tardis doesnít mind if w32time is running too much but w32time doesnít like Tardis using the same resources. If you can arrange w32time to start first you can just about get away with running them both.

Tardis basically does the same job as w32time (but better obviously). Why would you want to use w32time? Tardis is NTP compliant too.