AIMMS Knowledge Base Article – KB000008

No hardware key found


Sometimes AIMMS cannot find the security dongle, for example because the driver for the dongle is not installed.


When you startup AIMMS, the following error message might occur:

        AIMMS Initialization Error: No hardware key found and no keyless license file found.


There are several causes for this problem:

  • You have a parallel security dongle and you are using Windows 2000 in combination with certain HP printers.
  • The driver installation for the hardware key was not successful.
  • The port to which the hardware key is attached is not working properly.
  • The hardware key is defect.


If you are using Windows 2000 in combination with certain HP printers (e.g. HP LaserJet 3100), the printer may control the parallel port to the extent that the dongle driver cannot access the parallel port anymore. If the problem disappears when you disconnect the printer and remove the printer driver from your computer, you may request a USB dongle, upgrade to the latest Sentinel drivers, and disable the driver for the parallel port to resolve the problem.

If this is not the case, it is a good idea to check whether the dongle works on another computer (preferably a computer that this dongle, or another AIMMS dongle of the same type, has previously worked on). If you have another AIMMS dongle of the same type available, which does work on another computer, it is also a good idea to check whether this AIMMS dongle works on the ‘problem’ computer.

If the problem dongle gives the same error on a computer on which another AIMMS dongle of the same type works, it is very likely broken. In this case you should replace it, contact us at for the procedure for replacing a dongle.

If another AIMMS dongle of the same type that does work on another computer does not work on the problem computer, there is probably a driver problem. Make sure that the dongle drivers are installed correctly. In the Bin folder of AIMMS is a program called querykey.exe that checks the connection of the hardware key.

The actual (gray parallel and purple USB) dongle drivers are installed during the AIMMS installation in the folder \Program Files\Paragon Decision Technology\ Common\Sentinel. You can run the SetupSysDriver.exe program to see if the driver is activated and to see if it finds the dongle.

A separate installation for the purple USB and gray dongles can be downloaded from our ftp site. It might be necessary to run this installation if you are using USB dongles with an older version of AIMMS, since AIMMS 3.2.939 is the first version for which the USB driver is automatically installed.

The green parallel dongle drivers used to be installed in a Key subfolder of AIMMS in early AIMMS 3 installations, but are no longer part of the AIMMS 3 installation. These green dongle drivers can be downloaded from our ftp site.

If you are working with a green dongle, and you have installed the drivers, but you still get the same error message, while the dongle does work on (some) other computers, please see “Problem with green dongle”.

If these tips fail, there is a more elaborate document with suggestions from the dongle supplier, Rainbow Technologies, which can be found here.

More information

For more information, please contact us at

Last reviewed: 01-06-2005